Split mutex.c and .h each into three files
[fio.git] / server.c
index 519a7ee..959786f 100644 (file)
--- a/server.c
+++ b/server.c
@@ -32,7 +32,24 @@ int fio_net_port = FIO_NET_PORT;
 
 int exit_backend = 0;
 
-static int server_fd = -1;
+enum {
+       SK_F_FREE       = 1,
+       SK_F_COPY       = 2,
+       SK_F_SIMPLE     = 4,
+       SK_F_VEC        = 8,
+       SK_F_INLINE     = 16,
+};
+
+struct sk_entry {
+       struct flist_head list; /* link on sk_out->list */
+       int flags;              /* SK_F_* */
+       int opcode;             /* Actual command fields */
+       void *buf;
+       off_t size;
+       uint64_t tag;
+       struct flist_head next; /* Other sk_entry's, if linked command */
+};
+
 static char *fio_server_arg;
 static char *bind_sock;
 static struct sockaddr_in saddr_in;
@@ -46,6 +63,8 @@ static unsigned int has_zlib = 0;
 static unsigned int use_zlib;
 static char me[128];
 
+static pthread_key_t sk_out_key;
+
 struct fio_fork_item {
        struct flist_head list;
        int exitval;
@@ -84,8 +103,87 @@ static const char *fio_server_ops[FIO_NET_CMD_NR] = {
        "LOAD_FILE",
        "VTRIGGER",
        "SENDFILE",
+       "JOB_OPT",
 };
 
+static void sk_lock(struct sk_out *sk_out)
+{
+       fio_mutex_down(&sk_out->lock);
+}
+
+static void sk_unlock(struct sk_out *sk_out)
+{
+       fio_mutex_up(&sk_out->lock);
+}
+
+void sk_out_assign(struct sk_out *sk_out)
+{
+       if (!sk_out)
+               return;
+
+       sk_lock(sk_out);
+       sk_out->refs++;
+       sk_unlock(sk_out);
+       pthread_setspecific(sk_out_key, sk_out);
+}
+
+static void sk_out_free(struct sk_out *sk_out)
+{
+       __fio_mutex_remove(&sk_out->lock);
+       __fio_mutex_remove(&sk_out->wait);
+       __fio_mutex_remove(&sk_out->xmit);
+       sfree(sk_out);
+}
+
+static int __sk_out_drop(struct sk_out *sk_out)
+{
+       if (sk_out) {
+               int refs;
+
+               sk_lock(sk_out);
+               assert(sk_out->refs != 0);
+               refs = --sk_out->refs;
+               sk_unlock(sk_out);
+
+               if (!refs) {
+                       sk_out_free(sk_out);
+                       pthread_setspecific(sk_out_key, NULL);
+                       return 0;
+               }
+       }
+
+       return 1;
+}
+
+void sk_out_drop(void)
+{
+       struct sk_out *sk_out;
+
+       sk_out = pthread_getspecific(sk_out_key);
+       __sk_out_drop(sk_out);
+}
+
+static void __fio_init_net_cmd(struct fio_net_cmd *cmd, uint16_t opcode,
+                              uint32_t pdu_len, uint64_t tag)
+{
+       memset(cmd, 0, sizeof(*cmd));
+
+       cmd->version    = __cpu_to_le16(FIO_SERVER_VER);
+       cmd->opcode     = cpu_to_le16(opcode);
+       cmd->tag        = cpu_to_le64(tag);
+       cmd->pdu_len    = cpu_to_le32(pdu_len);
+}
+
+
+static void fio_init_net_cmd(struct fio_net_cmd *cmd, uint16_t opcode,
+                            const void *pdu, uint32_t pdu_len, uint64_t tag)
+{
+       __fio_init_net_cmd(cmd, opcode, pdu_len, tag);
+
+       if (pdu)
+               memcpy(&cmd->payload, pdu, pdu_len);
+}
+
 const char *fio_server_op(unsigned int op)
 {
        static char buf[32];
@@ -142,13 +240,10 @@ static int fio_sendv_data(int sk, struct iovec *iov, int count)
        if (!total_len)
                return 0;
 
-       if (errno)
-               return -errno;
-
        return 1;
 }
 
-int fio_send_data(int sk, const void *p, unsigned int len)
+static int fio_send_data(int sk, const void *p, unsigned int len)
 {
        struct iovec iov = { .iov_base = (void *) p, .iov_len = len };
 
@@ -157,10 +252,18 @@ int fio_send_data(int sk, const void *p, unsigned int len)
        return fio_sendv_data(sk, &iov, 1);
 }
 
-int fio_recv_data(int sk, void *p, unsigned int len)
+static int fio_recv_data(int sk, void *buf, unsigned int len, bool wait)
 {
+       int flags;
+       char *p = buf;
+
+       if (wait)
+               flags = MSG_WAITALL;
+       else
+               flags = OS_MSG_DONTWAIT;
+
        do {
-               int ret = recv(sk, p, len, MSG_WAITALL);
+               int ret = recv(sk, p, len, flags);
 
                if (ret > 0) {
                        len -= ret;
@@ -170,9 +273,11 @@ int fio_recv_data(int sk, void *p, unsigned int len)
                        continue;
                } else if (!ret)
                        break;
-               else if (errno == EAGAIN || errno == EINTR)
-                       continue;
-               else
+               else if (errno == EAGAIN || errno == EINTR) {
+                       if (wait)
+                               continue;
+                       break;
+               } else
                        break;
        } while (!exit_backend);
 
@@ -221,7 +326,7 @@ static int verify_convert_cmd(struct fio_net_cmd *cmd)
 /*
  * Read (and defragment, if necessary) incoming commands
  */
-struct fio_net_cmd *fio_net_recv_cmd(int sk)
+struct fio_net_cmd *fio_net_recv_cmd(int sk, bool wait)
 {
        struct fio_net_cmd cmd, *tmp, *cmdret = NULL;
        size_t cmd_size = 0, pdu_offset = 0;
@@ -230,7 +335,7 @@ struct fio_net_cmd *fio_net_recv_cmd(int sk)
        void *pdu = NULL;
 
        do {
-               ret = fio_recv_data(sk, &cmd, sizeof(cmd));
+               ret = fio_recv_data(sk, &cmd, sizeof(cmd), wait);
                if (ret)
                        break;
 
@@ -273,8 +378,8 @@ struct fio_net_cmd *fio_net_recv_cmd(int sk)
                        break;
 
                /* There's payload, get it */
-               pdu = (void *) cmdret->payload + pdu_offset;
-               ret = fio_recv_data(sk, pdu, cmd.pdu_len);
+               pdu = (char *) cmdret->payload + pdu_offset;
+               ret = fio_recv_data(sk, pdu, cmd.pdu_len, wait);
                if (ret)
                        break;
 
@@ -334,7 +439,7 @@ static uint64_t alloc_reply(uint64_t tag, uint16_t opcode)
 
        reply = calloc(1, sizeof(*reply));
        INIT_FLIST_HEAD(&reply->list);
-       fio_gettime(&reply->tv, NULL);
+       fio_gettime(&reply->ts, NULL);
        reply->saved_tag = tag;
        reply->opcode = opcode;
 
@@ -349,7 +454,7 @@ static void free_reply(uint64_t tag)
        free(reply);
 }
 
-void fio_net_cmd_crc_pdu(struct fio_net_cmd *cmd, const void *pdu)
+static void fio_net_cmd_crc_pdu(struct fio_net_cmd *cmd, const void *pdu)
 {
        uint32_t pdu_len;
 
@@ -359,7 +464,7 @@ void fio_net_cmd_crc_pdu(struct fio_net_cmd *cmd, const void *pdu)
        cmd->pdu_crc16 = __cpu_to_le16(fio_crc16(pdu, pdu_len));
 }
 
-void fio_net_cmd_crc(struct fio_net_cmd *cmd)
+static void fio_net_cmd_crc(struct fio_net_cmd *cmd)
 {
        fio_net_cmd_crc_pdu(cmd, cmd->payload);
 }
@@ -416,6 +521,61 @@ int fio_net_send_cmd(int fd, uint16_t opcode, const void *buf, off_t size,
        return ret;
 }
 
+static struct sk_entry *fio_net_prep_cmd(uint16_t opcode, void *buf,
+                                        size_t size, uint64_t *tagptr,
+                                        int flags)
+{
+       struct sk_entry *entry;
+
+       entry = smalloc(sizeof(*entry));
+       INIT_FLIST_HEAD(&entry->next);
+       entry->opcode = opcode;
+       if (flags & SK_F_COPY) {
+               entry->buf = smalloc(size);
+               memcpy(entry->buf, buf, size);
+       } else
+               entry->buf = buf;
+
+       entry->size = size;
+       if (tagptr)
+               entry->tag = *tagptr;
+       else
+               entry->tag = 0;
+       entry->flags = flags;
+       return entry;
+}
+
+static int handle_sk_entry(struct sk_out *sk_out, struct sk_entry *entry);
+
+static void fio_net_queue_entry(struct sk_entry *entry)
+{
+       struct sk_out *sk_out = pthread_getspecific(sk_out_key);
+
+       if (entry->flags & SK_F_INLINE)
+               handle_sk_entry(sk_out, entry);
+       else {
+               sk_lock(sk_out);
+               flist_add_tail(&entry->list, &sk_out->list);
+               sk_unlock(sk_out);
+
+               fio_mutex_up(&sk_out->wait);
+       }
+}
+
+static int fio_net_queue_cmd(uint16_t opcode, void *buf, off_t size,
+                            uint64_t *tagptr, int flags)
+{
+       struct sk_entry *entry;
+
+       entry = fio_net_prep_cmd(opcode, buf, size, tagptr, flags);
+       if (entry) {
+               fio_net_queue_entry(entry);
+               return 0;
+       }
+
+       return 1;
+}
+
 static int fio_net_send_simple_stack_cmd(int sk, uint16_t opcode, uint64_t tag)
 {
        struct fio_net_cmd cmd;
@@ -452,6 +612,13 @@ int fio_net_send_simple_cmd(int sk, uint16_t opcode, uint64_t tag,
        return 0;
 }
 
+static int fio_net_queue_quit(void)
+{
+       dprint(FD_NET, "server: sending quit\n");
+
+       return fio_net_queue_cmd(FIO_NET_CMD_QUIT, NULL, 0, NULL, SK_F_SIMPLE | SK_F_INLINE);
+}
+
 int fio_net_send_quit(int sk)
 {
        dprint(FD_NET, "server: sending quit\n");
@@ -459,8 +626,7 @@ int fio_net_send_quit(int sk)
        return fio_net_send_simple_cmd(sk, FIO_NET_CMD_QUIT, 0, NULL);
 }
 
-static int fio_net_send_ack(int sk, struct fio_net_cmd *cmd, int error,
-                           int signal)
+static int fio_net_send_ack(struct fio_net_cmd *cmd, int error, int signal)
 {
        struct cmd_end_pdu epdu;
        uint64_t tag = 0;
@@ -470,13 +636,13 @@ static int fio_net_send_ack(int sk, struct fio_net_cmd *cmd, int error,
 
        epdu.error = __cpu_to_le32(error);
        epdu.signal = __cpu_to_le32(signal);
-       return fio_net_send_cmd(sk, FIO_NET_CMD_STOP, &epdu, sizeof(epdu), &tag, NULL);
+       return fio_net_queue_cmd(FIO_NET_CMD_STOP, &epdu, sizeof(epdu), &tag, SK_F_COPY | SK_F_INLINE);
 }
 
-int fio_net_send_stop(int sk, int error, int signal)
+static int fio_net_queue_stop(int error, int signal)
 {
        dprint(FD_NET, "server: sending stop (%d, %d)\n", error, signal);
-       return fio_net_send_ack(sk, NULL, error, signal);
+       return fio_net_send_ack(NULL, error, signal);
 }
 
 static void fio_server_add_fork_item(pid_t pid, struct flist_head *list)
@@ -527,20 +693,23 @@ static void fio_server_check_fork_item(struct fio_fork_item *ffi)
        }
 }
 
-static void fio_server_fork_item_done(struct fio_fork_item *ffi)
+static void fio_server_fork_item_done(struct fio_fork_item *ffi, bool stop)
 {
        dprint(FD_NET, "pid %u exited, sig=%u, exitval=%d\n", (int) ffi->pid, ffi->signal, ffi->exitval);
 
        /*
         * Fold STOP and QUIT...
         */
-       fio_net_send_stop(server_fd, ffi->exitval, ffi->signal);
-       fio_net_send_quit(server_fd);
+       if (stop) {
+               fio_net_queue_stop(ffi->exitval, ffi->signal);
+               fio_net_queue_quit();
+       }
+
        flist_del(&ffi->list);
        free(ffi);
 }
 
-static void fio_server_check_fork_items(struct flist_head *list)
+static void fio_server_check_fork_items(struct flist_head *list, bool stop)
 {
        struct flist_head *entry, *tmp;
        struct fio_fork_item *ffi;
@@ -551,18 +720,18 @@ static void fio_server_check_fork_items(struct flist_head *list)
                fio_server_check_fork_item(ffi);
 
                if (ffi->exited)
-                       fio_server_fork_item_done(ffi);
+                       fio_server_fork_item_done(ffi, stop);
        }
 }
 
 static void fio_server_check_jobs(struct flist_head *job_list)
 {
-       fio_server_check_fork_items(job_list);
+       fio_server_check_fork_items(job_list, true);
 }
 
 static void fio_server_check_conns(struct flist_head *conn_list)
 {
-       fio_server_check_fork_items(conn_list);
+       fio_server_check_fork_items(conn_list, false);
 }
 
 static int handle_load_file_cmd(struct fio_net_cmd *cmd)
@@ -577,21 +746,24 @@ static int handle_load_file_cmd(struct fio_net_cmd *cmd)
        pdu->client_type = le16_to_cpu(pdu->client_type);
 
        if (parse_jobs_ini(file_name, 0, 0, pdu->client_type)) {
-               fio_net_send_quit(server_fd);
+               fio_net_queue_quit();
                return -1;
        }
 
        spdu.jobs = cpu_to_le32(thread_number);
        spdu.stat_outputs = cpu_to_le32(stat_number);
-       fio_net_send_cmd(server_fd, FIO_NET_CMD_START, &spdu, sizeof(spdu), NULL, NULL);
+       fio_net_queue_cmd(FIO_NET_CMD_START, &spdu, sizeof(spdu), NULL, SK_F_COPY);
        return 0;
 }
 
-static int handle_run_cmd(struct flist_head *job_list, struct fio_net_cmd *cmd)
+static int handle_run_cmd(struct sk_out *sk_out, struct flist_head *job_list,
+                         struct fio_net_cmd *cmd)
 {
        pid_t pid;
        int ret;
 
+       sk_out_assign(sk_out);
+
        fio_time_init();
        set_genesis_time();
 
@@ -601,8 +773,9 @@ static int handle_run_cmd(struct flist_head *job_list, struct fio_net_cmd *cmd)
                return 0;
        }
 
-       ret = fio_backend();
+       ret = fio_backend(sk_out);
        free_threads_shm();
+       sk_out_drop();
        _exit(ret);
 }
 
@@ -616,13 +789,14 @@ static int handle_job_cmd(struct fio_net_cmd *cmd)
        pdu->client_type = le32_to_cpu(pdu->client_type);
 
        if (parse_jobs_ini(buf, 1, 0, pdu->client_type)) {
-               fio_net_send_quit(server_fd);
+               fio_net_queue_quit();
                return -1;
        }
 
        spdu.jobs = cpu_to_le32(thread_number);
        spdu.stat_outputs = cpu_to_le32(stat_number);
-       fio_net_send_cmd(server_fd, FIO_NET_CMD_START, &spdu, sizeof(spdu), NULL, NULL);
+
+       fio_net_queue_cmd(FIO_NET_CMD_START, &spdu, sizeof(spdu), NULL, SK_F_COPY);
        return 0;
 }
 
@@ -653,7 +827,7 @@ static int handle_jobline_cmd(struct fio_net_cmd *cmd)
        }
 
        if (parse_cmd_line(clp->lines, argv, clp->client_type)) {
-               fio_net_send_quit(server_fd);
+               fio_net_queue_quit();
                free(argv);
                return -1;
        }
@@ -662,31 +836,31 @@ static int handle_jobline_cmd(struct fio_net_cmd *cmd)
 
        spdu.jobs = cpu_to_le32(thread_number);
        spdu.stat_outputs = cpu_to_le32(stat_number);
-       fio_net_send_cmd(server_fd, FIO_NET_CMD_START, &spdu, sizeof(spdu), NULL, NULL);
+
+       fio_net_queue_cmd(FIO_NET_CMD_START, &spdu, sizeof(spdu), NULL, SK_F_COPY);
        return 0;
 }
 
 static int handle_probe_cmd(struct fio_net_cmd *cmd)
 {
        struct cmd_client_probe_pdu *pdu = (struct cmd_client_probe_pdu *) cmd->payload;
-       struct cmd_probe_reply_pdu probe;
        uint64_t tag = cmd->tag;
+       struct cmd_probe_reply_pdu probe = {
+#ifdef CONFIG_BIG_ENDIAN
+               .bigendian      = 1,
+#endif
+               .os             = FIO_OS,
+               .arch           = FIO_ARCH,
+               .bpp            = sizeof(void *),
+               .cpus           = __cpu_to_le32(cpus_online()),
+       };
 
        dprint(FD_NET, "server: sending probe reply\n");
 
        strcpy(me, (char *) pdu->server);
 
-       memset(&probe, 0, sizeof(probe));
        gethostname((char *) probe.hostname, sizeof(probe.hostname));
-#ifdef CONFIG_BIG_ENDIAN
-       probe.bigendian = 1;
-#endif
-       strncpy((char *) probe.fio_version, fio_version_string, sizeof(probe.fio_version));
-
-       probe.os        = FIO_OS;
-       probe.arch      = FIO_ARCH;
-       probe.bpp       = sizeof(void *);
-       probe.cpus      = __cpu_to_le32(cpus_online());
+       strncpy((char *) probe.fio_version, fio_version_string, sizeof(probe.fio_version) - 1);
 
        /*
         * If the client supports compression and we do too, then enable it
@@ -699,7 +873,7 @@ static int handle_probe_cmd(struct fio_net_cmd *cmd)
                use_zlib = 0;
        }
 
-       return fio_net_send_cmd(server_fd, FIO_NET_CMD_PROBE, &probe, sizeof(probe), &tag, NULL);
+       return fio_net_queue_cmd(FIO_NET_CMD_PROBE, &probe, sizeof(probe), &tag, SK_F_COPY);
 }
 
 static int handle_send_eta_cmd(struct fio_net_cmd *cmd)
@@ -709,45 +883,50 @@ static int handle_send_eta_cmd(struct fio_net_cmd *cmd)
        size_t size;
        int i;
 
-       je = get_jobs_eta(1, &size);
-       if (!je)
-               return 0;
-
        dprint(FD_NET, "server sending status\n");
 
-       je->nr_running          = cpu_to_le32(je->nr_running);
-       je->nr_ramp             = cpu_to_le32(je->nr_ramp);
-       je->nr_pending          = cpu_to_le32(je->nr_pending);
-       je->nr_setting_up       = cpu_to_le32(je->nr_setting_up);
-       je->files_open          = cpu_to_le32(je->files_open);
+       /*
+        * Fake ETA return if we don't have a local one, otherwise the client
+        * will end up timing out waiting for a response to the ETA request
+        */
+       je = get_jobs_eta(true, &size);
+       if (!je) {
+               size = sizeof(*je);
+               je = calloc(1, size);
+       } else {
+               je->nr_running          = cpu_to_le32(je->nr_running);
+               je->nr_ramp             = cpu_to_le32(je->nr_ramp);
+               je->nr_pending          = cpu_to_le32(je->nr_pending);
+               je->nr_setting_up       = cpu_to_le32(je->nr_setting_up);
+               je->files_open          = cpu_to_le32(je->files_open);
+
+               for (i = 0; i < DDIR_RWDIR_CNT; i++) {
+                       je->m_rate[i]   = cpu_to_le64(je->m_rate[i]);
+                       je->t_rate[i]   = cpu_to_le64(je->t_rate[i]);
+                       je->m_iops[i]   = cpu_to_le32(je->m_iops[i]);
+                       je->t_iops[i]   = cpu_to_le32(je->t_iops[i]);
+                       je->rate[i]     = cpu_to_le64(je->rate[i]);
+                       je->iops[i]     = cpu_to_le32(je->iops[i]);
+               }
 
-       for (i = 0; i < DDIR_RWDIR_CNT; i++) {
-               je->m_rate[i]   = cpu_to_le32(je->m_rate[i]);
-               je->t_rate[i]   = cpu_to_le32(je->t_rate[i]);
-               je->m_iops[i]   = cpu_to_le32(je->m_iops[i]);
-               je->t_iops[i]   = cpu_to_le32(je->t_iops[i]);
-               je->rate[i]     = cpu_to_le32(je->rate[i]);
-               je->iops[i]     = cpu_to_le32(je->iops[i]);
-       }
-
-       je->elapsed_sec         = cpu_to_le64(je->elapsed_sec);
-       je->eta_sec             = cpu_to_le64(je->eta_sec);
-       je->nr_threads          = cpu_to_le32(je->nr_threads);
-       je->is_pow2             = cpu_to_le32(je->is_pow2);
-       je->unit_base           = cpu_to_le32(je->unit_base);
-
-       fio_net_send_cmd(server_fd, FIO_NET_CMD_ETA, je, size, &tag, NULL);
-       free(je);
+               je->elapsed_sec         = cpu_to_le64(je->elapsed_sec);
+               je->eta_sec             = cpu_to_le64(je->eta_sec);
+               je->nr_threads          = cpu_to_le32(je->nr_threads);
+               je->is_pow2             = cpu_to_le32(je->is_pow2);
+               je->unit_base           = cpu_to_le32(je->unit_base);
+       }
+
+       fio_net_queue_cmd(FIO_NET_CMD_ETA, je, size, &tag, SK_F_FREE);
        return 0;
 }
 
-static int send_update_job_reply(int fd, uint64_t __tag, int error)
+static int send_update_job_reply(uint64_t __tag, int error)
 {
        uint64_t tag = __tag;
        uint32_t pdu_error;
 
        pdu_error = __cpu_to_le32(error);
-       return fio_net_send_cmd(fd, FIO_NET_CMD_UPDATE_JOB, &pdu_error, sizeof(pdu_error), &tag, NULL);
+       return fio_net_queue_cmd(FIO_NET_CMD_UPDATE_JOB, &pdu_error, sizeof(pdu_error), &tag, SK_F_COPY);
 }
 
 static int handle_update_job_cmd(struct fio_net_cmd *cmd)
@@ -761,17 +940,17 @@ static int handle_update_job_cmd(struct fio_net_cmd *cmd)
        dprint(FD_NET, "server: updating options for job %u\n", tnumber);
 
        if (!tnumber || tnumber > thread_number) {
-               send_update_job_reply(server_fd, cmd->tag, ENODEV);
+               send_update_job_reply(cmd->tag, ENODEV);
                return 0;
        }
 
        td = &threads[tnumber - 1];
        convert_thread_options_to_cpu(&td->o, &pdu->top);
-       send_update_job_reply(server_fd, cmd->tag, 0);
+       send_update_job_reply(cmd->tag, 0);
        return 0;
 }
 
-static int handle_trigger_cmd(struct fio_net_cmd *cmd)
+static int handle_trigger_cmd(struct fio_net_cmd *cmd, struct flist_head *job_list)
 {
        struct cmd_vtrigger_pdu *pdu = (struct cmd_vtrigger_pdu *) cmd->payload;
        char *buf = (char *) pdu->cmd;
@@ -786,17 +965,18 @@ static int handle_trigger_cmd(struct fio_net_cmd *cmd)
                struct all_io_list state;
 
                state.threads = cpu_to_le64((uint64_t) 0);
-               fio_net_send_cmd(server_fd, FIO_NET_CMD_VTRIGGER, &state, sizeof(state), NULL, NULL);
-       } else {
-               fio_net_send_cmd(server_fd, FIO_NET_CMD_VTRIGGER, rep, sz, NULL, NULL);
-               free(rep);
-       }
+               fio_net_queue_cmd(FIO_NET_CMD_VTRIGGER, &state, sizeof(state), NULL, SK_F_COPY | SK_F_INLINE);
+       } else
+               fio_net_queue_cmd(FIO_NET_CMD_VTRIGGER, rep, sz, NULL, SK_F_FREE | SK_F_INLINE);
 
+       fio_terminate_threads(TERMINATE_ALL);
+       fio_server_check_jobs(job_list);
        exec_trigger(buf);
        return 0;
 }
 
-static int handle_command(struct flist_head *job_list, struct fio_net_cmd *cmd)
+static int handle_command(struct sk_out *sk_out, struct flist_head *job_list,
+                         struct fio_net_cmd *cmd)
 {
        int ret;
 
@@ -807,7 +987,8 @@ static int handle_command(struct flist_head *job_list, struct fio_net_cmd *cmd)
        switch (cmd->opcode) {
        case FIO_NET_CMD_QUIT:
                fio_terminate_threads(TERMINATE_ALL);
-               return -1;
+               ret = 0;
+               break;
        case FIO_NET_CMD_EXIT:
                exit_backend = 1;
                return -1;
@@ -827,13 +1008,13 @@ static int handle_command(struct flist_head *job_list, struct fio_net_cmd *cmd)
                ret = handle_send_eta_cmd(cmd);
                break;
        case FIO_NET_CMD_RUN:
-               ret = handle_run_cmd(job_list, cmd);
+               ret = handle_run_cmd(sk_out, job_list, cmd);
                break;
        case FIO_NET_CMD_UPDATE_JOB:
                ret = handle_update_job_cmd(cmd);
                break;
        case FIO_NET_CMD_VTRIGGER:
-               ret = handle_trigger_cmd(cmd);
+               ret = handle_trigger_cmd(cmd, job_list);
                break;
        case FIO_NET_CMD_SENDFILE: {
                struct cmd_sendfile_reply *in;
@@ -869,19 +1050,151 @@ static int handle_command(struct flist_head *job_list, struct fio_net_cmd *cmd)
        return ret;
 }
 
-static int handle_connection(int sk)
+/*
+ * Send a command with a separate PDU, not inlined in the command
+ */
+static int fio_send_cmd_ext_pdu(int sk, uint16_t opcode, const void *buf,
+                               off_t size, uint64_t tag, uint32_t flags)
+{
+       struct fio_net_cmd cmd;
+       struct iovec iov[2];
+       size_t this_len;
+       int ret;
+
+       iov[0].iov_base = (void *) &cmd;
+       iov[0].iov_len = sizeof(cmd);
+
+       do {
+               uint32_t this_flags = flags;
+
+               this_len = size;
+               if (this_len > FIO_SERVER_MAX_FRAGMENT_PDU)
+                       this_len = FIO_SERVER_MAX_FRAGMENT_PDU;
+
+               if (this_len < size)
+                       this_flags |= FIO_NET_CMD_F_MORE;
+
+               __fio_init_net_cmd(&cmd, opcode, this_len, tag);
+               cmd.flags = __cpu_to_le32(this_flags);
+               fio_net_cmd_crc_pdu(&cmd, buf);
+
+               iov[1].iov_base = (void *) buf;
+               iov[1].iov_len = this_len;
+
+               ret = fio_sendv_data(sk, iov, 2);
+               size -= this_len;
+               buf += this_len;
+       } while (!ret && size);
+
+       return ret;
+}
+
+static void finish_entry(struct sk_entry *entry)
+{
+       if (entry->flags & SK_F_FREE)
+               free(entry->buf);
+       else if (entry->flags & SK_F_COPY)
+               sfree(entry->buf);
+
+       sfree(entry);
+}
+
+static void entry_set_flags(struct sk_entry *entry, struct flist_head *list,
+                           unsigned int *flags)
+{
+       if (!flist_empty(list))
+               *flags = FIO_NET_CMD_F_MORE;
+       else
+               *flags = 0;
+}
+
+static int send_vec_entry(struct sk_out *sk_out, struct sk_entry *first)
+{
+       unsigned int flags;
+       int ret;
+
+       entry_set_flags(first, &first->next, &flags);
+
+       ret = fio_send_cmd_ext_pdu(sk_out->sk, first->opcode, first->buf,
+                                       first->size, first->tag, flags);
+
+       while (!flist_empty(&first->next)) {
+               struct sk_entry *next;
+
+               next = flist_first_entry(&first->next, struct sk_entry, list);
+               flist_del_init(&next->list);
+
+               entry_set_flags(next, &first->next, &flags);
+
+               ret += fio_send_cmd_ext_pdu(sk_out->sk, next->opcode, next->buf,
+                                               next->size, next->tag, flags);
+               finish_entry(next);
+       }
+
+       return ret;
+}
+
+static int handle_sk_entry(struct sk_out *sk_out, struct sk_entry *entry)
+{
+       int ret;
+
+       fio_mutex_down(&sk_out->xmit);
+
+       if (entry->flags & SK_F_VEC)
+               ret = send_vec_entry(sk_out, entry);
+       else if (entry->flags & SK_F_SIMPLE) {
+               ret = fio_net_send_simple_cmd(sk_out->sk, entry->opcode,
+                                               entry->tag, NULL);
+       } else {
+               ret = fio_net_send_cmd(sk_out->sk, entry->opcode, entry->buf,
+                                       entry->size, &entry->tag, NULL);
+       }
+
+       fio_mutex_up(&sk_out->xmit);
+
+       if (ret)
+               log_err("fio: failed handling cmd %s\n", fio_server_op(entry->opcode));
+
+       finish_entry(entry);
+       return ret;
+}
+
+static int handle_xmits(struct sk_out *sk_out)
+{
+       struct sk_entry *entry;
+       FLIST_HEAD(list);
+       int ret = 0;
+
+       sk_lock(sk_out);
+       if (flist_empty(&sk_out->list)) {
+               sk_unlock(sk_out);
+               return 0;
+       }
+
+       flist_splice_init(&sk_out->list, &list);
+       sk_unlock(sk_out);
+
+       while (!flist_empty(&list)) {
+               entry = flist_entry(list.next, struct sk_entry, list);
+               flist_del(&entry->list);
+               ret += handle_sk_entry(sk_out, entry);
+       }
+
+       return ret;
+}
+
+static int handle_connection(struct sk_out *sk_out)
 {
        struct fio_net_cmd *cmd = NULL;
        FLIST_HEAD(job_list);
        int ret = 0;
 
        reset_fio_state();
-       server_fd = sk;
 
        /* read forever */
        while (!exit_backend) {
                struct pollfd pfd = {
-                       .fd     = sk,
+                       .fd     = sk_out->sk,
                        .events = POLLIN,
                };
 
@@ -892,7 +1205,9 @@ static int handle_connection(int sk)
                        if (!flist_empty(&job_list))
                                timeout = 100;
 
-                       ret = poll(&pfd, 1, timeout);
+                       handle_xmits(sk_out);
+
+                       ret = poll(&pfd, 1, 0);
                        if (ret < 0) {
                                if (errno == EINTR)
                                        break;
@@ -900,6 +1215,7 @@ static int handle_connection(int sk)
                                break;
                        } else if (!ret) {
                                fio_server_check_jobs(&job_list);
+                               fio_mutex_down_timeout(&sk_out->wait, timeout);
                                continue;
                        }
 
@@ -916,13 +1232,13 @@ static int handle_connection(int sk)
                if (ret < 0)
                        break;
 
-               cmd = fio_net_recv_cmd(sk);
+               cmd = fio_net_recv_cmd(sk_out->sk, true);
                if (!cmd) {
                        ret = -1;
                        break;
                }
 
-               ret = handle_command(&job_list, cmd);
+               ret = handle_command(sk_out, &job_list, cmd);
                if (ret)
                        break;
 
@@ -933,39 +1249,47 @@ static int handle_connection(int sk)
        if (cmd)
                free(cmd);
 
-       close(sk);
+       handle_xmits(sk_out);
+
+       close(sk_out->sk);
+       sk_out->sk = -1;
+       __sk_out_drop(sk_out);
        _exit(ret);
 }
 
 /* get the address on this host bound by the input socket, 
  * whether it is ipv6 or ipv4 */
 
-int get_my_addr_str( int sk )
+static int get_my_addr_str(int sk)
 {
-       int ret; 
-       struct sockaddr * sockaddr_p;
-       struct sockaddr_in myaddr4 = {0};
-       struct sockaddr_in6 myaddr6 = {0};
-       char * net_addr;
-       socklen_t len = use_ipv6 ? sizeof(myaddr6) : sizeof(myaddr4);
+       struct sockaddr_in6 myaddr6 = { 0, };
+       struct sockaddr_in myaddr4 = { 0, };
+       struct sockaddr *sockaddr_p;
+       char *net_addr;
+       socklen_t len;
+       int ret;
 
-       if (use_ipv6)
+       if (use_ipv6) {
+               len = sizeof(myaddr6);
                sockaddr_p = (struct sockaddr * )&myaddr6;
-       else
+               net_addr = (char * )&myaddr6.sin6_addr;
+       } else {
+               len = sizeof(myaddr4);
                sockaddr_p = (struct sockaddr * )&myaddr4;
+               net_addr = (char * )&myaddr4.sin_addr;
+       }
+
        ret = getsockname(sk, sockaddr_p, &len);
        if (ret) {
-               log_err("fio: getsockaddr: %s\n", strerror(errno));
+               log_err("fio: getsockname: %s\n", strerror(errno));
                return -1;
        }
-       if (use_ipv6)
-               net_addr = (char * )&myaddr6.sin6_addr;
-       else
-               net_addr = (char * )&myaddr4.sin_addr;
-       if (NULL == inet_ntop(use_ipv6?AF_INET6:AF_INET, net_addr, client_sockaddr_str, INET6_ADDRSTRLEN-1)) {
+
+       if (!inet_ntop(use_ipv6?AF_INET6:AF_INET, net_addr, client_sockaddr_str, INET6_ADDRSTRLEN - 1)) {
                log_err("inet_ntop: failed to convert addr to string\n");
                return -1;
        }
+
        dprint(FD_NET, "fio server bound to addr %s\n", client_sockaddr_str);
        return 0;
 }
@@ -984,6 +1308,7 @@ static int accept_loop(int listen_sk)
        fio_set_fd_nonblocking(listen_sk, "server");
 
        while (!exit_backend) {
+               struct sk_out *sk_out;
                const char *from;
                char buf[64];
                pid_t pid;
@@ -1033,6 +1358,13 @@ static int accept_loop(int listen_sk)
 
                dprint(FD_NET, "server: connect from %s\n", from);
 
+               sk_out = smalloc(sizeof(*sk_out));
+               sk_out->sk = sk;
+               INIT_FLIST_HEAD(&sk_out->list);
+               __fio_mutex_init(&sk_out->lock, FIO_MUTEX_UNLOCKED);
+               __fio_mutex_init(&sk_out->wait, FIO_MUTEX_LOCKED);
+               __fio_mutex_init(&sk_out->xmit, FIO_MUTEX_UNLOCKED);
+
                pid = fork();
                if (pid) {
                        close(sk);
@@ -1040,9 +1372,15 @@ static int accept_loop(int listen_sk)
                        continue;
                }
 
-               /* exits */
-               get_my_addr_str(sk); /* if error, it's already logged, non-fatal */
-               handle_connection(sk);
+               /* if error, it's already logged, non-fatal */
+               get_my_addr_str(sk);
+
+               /*
+                * Assign sk_out here, it'll be dropped in handle_connection()
+                * since that function calls _exit() when done
+                */
+               sk_out_assign(sk_out);
+               handle_connection(sk_out);
        }
 
        return exitval;
@@ -1050,12 +1388,13 @@ static int accept_loop(int listen_sk)
 
 int fio_server_text_output(int level, const char *buf, size_t len)
 {
+       struct sk_out *sk_out = pthread_getspecific(sk_out_key);
        struct cmd_text_pdu *pdu;
        unsigned int tlen;
        struct timeval tv;
 
-       if (server_fd == -1)
-               return log_local_buf(buf, len);
+       if (!sk_out || sk_out->sk == -1)
+               return -1;
 
        tlen = sizeof(*pdu) + len;
        pdu = malloc(tlen);
@@ -1069,7 +1408,7 @@ int fio_server_text_output(int level, const char *buf, size_t len)
 
        memcpy(pdu->buf, buf, len);
 
-       fio_net_send_cmd(server_fd, FIO_NET_CMD_TEXT, pdu, tlen, NULL, NULL);
+       fio_net_queue_cmd(FIO_NET_CMD_TEXT, pdu, tlen, NULL, SK_F_COPY);
        free(pdu);
        return len;
 }
@@ -1096,7 +1435,7 @@ static void convert_gs(struct group_run_stats *dst, struct group_run_stats *src)
                dst->min_run[i]         = cpu_to_le64(src->min_run[i]);
                dst->max_bw[i]          = cpu_to_le64(src->max_bw[i]);
                dst->min_bw[i]          = cpu_to_le64(src->min_bw[i]);
-               dst->io_kb[i]           = cpu_to_le64(src->io_kb[i]);
+               dst->iobytes[i]         = cpu_to_le64(src->iobytes[i]);
                dst->agg[i]             = cpu_to_le64(src->agg[i]);
        }
 
@@ -1104,6 +1443,7 @@ static void convert_gs(struct group_run_stats *dst, struct group_run_stats *src)
        dst->unit_base  = cpu_to_le32(src->unit_base);
        dst->groupid    = cpu_to_le32(src->groupid);
        dst->unified_rw_rep     = cpu_to_le32(src->unified_rw_rep);
+       dst->sig_figs   = cpu_to_le32(src->sig_figs);
 }
 
 /*
@@ -1114,6 +1454,8 @@ void fio_server_send_ts(struct thread_stat *ts, struct group_run_stats *rs)
 {
        struct cmd_ts_pdu p;
        int i, j;
+       void *ss_buf;
+       uint64_t *ss_iops, *ss_bw;
 
        dprint(FD_NET, "server sending end stats\n");
 
@@ -1135,6 +1477,7 @@ void fio_server_send_ts(struct thread_stat *ts, struct group_run_stats *rs)
                convert_io_stat(&p.ts.slat_stat[i], &ts->slat_stat[i]);
                convert_io_stat(&p.ts.lat_stat[i], &ts->lat_stat[i]);
                convert_io_stat(&p.ts.bw_stat[i], &ts->bw_stat[i]);
+               convert_io_stat(&p.ts.iops_stat[i], &ts->iops_stat[i]);
        }
 
        p.ts.usr_time           = cpu_to_le64(ts->usr_time);
@@ -1142,7 +1485,8 @@ void fio_server_send_ts(struct thread_stat *ts, struct group_run_stats *rs)
        p.ts.ctx                = cpu_to_le64(ts->ctx);
        p.ts.minf               = cpu_to_le64(ts->minf);
        p.ts.majf               = cpu_to_le64(ts->majf);
-       p.ts.clat_percentiles   = cpu_to_le64(ts->clat_percentiles);
+       p.ts.clat_percentiles   = cpu_to_le32(ts->clat_percentiles);
+       p.ts.lat_percentiles    = cpu_to_le32(ts->lat_percentiles);
        p.ts.percentile_precision = cpu_to_le64(ts->percentile_precision);
 
        for (i = 0; i < FIO_IO_U_LIST_MAX_LEN; i++) {
@@ -1153,19 +1497,21 @@ void fio_server_send_ts(struct thread_stat *ts, struct group_run_stats *rs)
        }
 
        for (i = 0; i < FIO_IO_U_MAP_NR; i++) {
-               p.ts.io_u_map[i]        = cpu_to_le32(ts->io_u_map[i]);
-               p.ts.io_u_submit[i]     = cpu_to_le32(ts->io_u_submit[i]);
-               p.ts.io_u_complete[i]   = cpu_to_le32(ts->io_u_complete[i]);
+               p.ts.io_u_map[i]        = cpu_to_le64(ts->io_u_map[i]);
+               p.ts.io_u_submit[i]     = cpu_to_le64(ts->io_u_submit[i]);
+               p.ts.io_u_complete[i]   = cpu_to_le64(ts->io_u_complete[i]);
        }
 
-       for (i = 0; i < FIO_IO_U_LAT_U_NR; i++) {
-               p.ts.io_u_lat_u[i]      = cpu_to_le32(ts->io_u_lat_u[i]);
-               p.ts.io_u_lat_m[i]      = cpu_to_le32(ts->io_u_lat_m[i]);
-       }
+       for (i = 0; i < FIO_IO_U_LAT_N_NR; i++)
+               p.ts.io_u_lat_n[i]      = cpu_to_le64(ts->io_u_lat_n[i]);
+       for (i = 0; i < FIO_IO_U_LAT_U_NR; i++)
+               p.ts.io_u_lat_u[i]      = cpu_to_le64(ts->io_u_lat_u[i]);
+       for (i = 0; i < FIO_IO_U_LAT_M_NR; i++)
+               p.ts.io_u_lat_m[i]      = cpu_to_le64(ts->io_u_lat_m[i]);
 
        for (i = 0; i < DDIR_RWDIR_CNT; i++)
                for (j = 0; j < FIO_IO_U_PLAT_NR; j++)
-                       p.ts.io_u_plat[i][j] = cpu_to_le32(ts->io_u_plat[i][j]);
+                       p.ts.io_u_plat[i][j] = cpu_to_le64(ts->io_u_plat[i][j]);
 
        for (i = 0; i < DDIR_RWDIR_CNT; i++) {
                p.ts.total_io_u[i]      = cpu_to_le64(ts->total_io_u[i]);
@@ -1193,13 +1539,43 @@ void fio_server_send_ts(struct thread_stat *ts, struct group_run_stats *rs)
        p.ts.latency_window     = cpu_to_le64(ts->latency_window);
        p.ts.latency_percentile.u.i = cpu_to_le64(fio_double_to_uint64(ts->latency_percentile.u.f));
 
-       p.ts.nr_block_infos     = le64_to_cpu(ts->nr_block_infos);
+       p.ts.sig_figs           = cpu_to_le32(ts->sig_figs);
+
+       p.ts.nr_block_infos     = cpu_to_le64(ts->nr_block_infos);
        for (i = 0; i < p.ts.nr_block_infos; i++)
-               p.ts.block_infos[i] = le32_to_cpu(ts->block_infos[i]);
+               p.ts.block_infos[i] = cpu_to_le32(ts->block_infos[i]);
+
+       p.ts.ss_dur             = cpu_to_le64(ts->ss_dur);
+       p.ts.ss_state           = cpu_to_le32(ts->ss_state);
+       p.ts.ss_head            = cpu_to_le32(ts->ss_head);
+       p.ts.ss_limit.u.i       = cpu_to_le64(fio_double_to_uint64(ts->ss_limit.u.f));
+       p.ts.ss_slope.u.i       = cpu_to_le64(fio_double_to_uint64(ts->ss_slope.u.f));
+       p.ts.ss_deviation.u.i   = cpu_to_le64(fio_double_to_uint64(ts->ss_deviation.u.f));
+       p.ts.ss_criterion.u.i   = cpu_to_le64(fio_double_to_uint64(ts->ss_criterion.u.f));
 
        convert_gs(&p.rs, rs);
 
-       fio_net_send_cmd(server_fd, FIO_NET_CMD_TS, &p, sizeof(p), NULL, NULL);
+       dprint(FD_NET, "ts->ss_state = %d\n", ts->ss_state);
+       if (ts->ss_state & FIO_SS_DATA) {
+               dprint(FD_NET, "server sending steadystate ring buffers\n");
+
+               ss_buf = malloc(sizeof(p) + 2*ts->ss_dur*sizeof(uint64_t));
+
+               memcpy(ss_buf, &p, sizeof(p));
+
+               ss_iops = (uint64_t *) ((struct cmd_ts_pdu *)ss_buf + 1);
+               ss_bw = ss_iops + (int) ts->ss_dur;
+               for (i = 0; i < ts->ss_dur; i++) {
+                       ss_iops[i] = cpu_to_le64(ts->ss_iops_data[i]);
+                       ss_bw[i] = cpu_to_le64(ts->ss_bw_data[i]);
+               }
+
+               fio_net_queue_cmd(FIO_NET_CMD_TS, ss_buf, sizeof(p) + 2*ts->ss_dur*sizeof(uint64_t), NULL, SK_F_COPY);
+
+               free(ss_buf);
+       }
+       else
+               fio_net_queue_cmd(FIO_NET_CMD_TS, &p, sizeof(p), NULL, SK_F_COPY);
 }
 
 void fio_server_send_gs(struct group_run_stats *rs)
@@ -1209,7 +1585,48 @@ void fio_server_send_gs(struct group_run_stats *rs)
        dprint(FD_NET, "server sending group run stats\n");
 
        convert_gs(&gs, rs);
-       fio_net_send_cmd(server_fd, FIO_NET_CMD_GS, &gs, sizeof(gs), NULL, NULL);
+       fio_net_queue_cmd(FIO_NET_CMD_GS, &gs, sizeof(gs), NULL, SK_F_COPY);
+}
+
+void fio_server_send_job_options(struct flist_head *opt_list,
+                                unsigned int groupid)
+{
+       struct cmd_job_option pdu;
+       struct flist_head *entry;
+
+       if (flist_empty(opt_list))
+               return;
+
+       flist_for_each(entry, opt_list) {
+               struct print_option *p;
+               size_t len;
+
+               p = flist_entry(entry, struct print_option, list);
+               memset(&pdu, 0, sizeof(pdu));
+
+               if (groupid == -1U) {
+                       pdu.global = __cpu_to_le16(1);
+                       pdu.groupid = 0;
+               } else {
+                       pdu.global = 0;
+                       pdu.groupid = cpu_to_le32(groupid);
+               }
+               len = strlen(p->name);
+               if (len >= sizeof(pdu.name)) {
+                       len = sizeof(pdu.name) - 1;
+                       pdu.truncated = __cpu_to_le16(1);
+               }
+               memcpy(pdu.name, p->name, len);
+               if (p->value) {
+                       len = strlen(p->value);
+                       if (len >= sizeof(pdu.value)) {
+                               len = sizeof(pdu.value) - 1;
+                               pdu.truncated = __cpu_to_le16(1);
+                       }
+                       memcpy(pdu.value, p->value, len);
+               }
+               fio_net_queue_cmd(FIO_NET_CMD_JOB_OPT, &pdu, sizeof(pdu), NULL, SK_F_COPY);
+       }
 }
 
 static void convert_agg(struct disk_util_agg *dst, struct disk_util_agg *src)
@@ -1264,149 +1681,340 @@ void fio_server_send_du(void)
                convert_dus(&pdu.dus, &du->dus);
                convert_agg(&pdu.agg, &du->agg);
 
-               fio_net_send_cmd(server_fd, FIO_NET_CMD_DU, &pdu, sizeof(pdu), NULL, NULL);
+               fio_net_queue_cmd(FIO_NET_CMD_DU, &pdu, sizeof(pdu), NULL, SK_F_COPY);
        }
 }
 
+#ifdef CONFIG_ZLIB
+
+static inline void __fio_net_prep_tail(z_stream *stream, void *out_pdu,
+                                       struct sk_entry **last_entry,
+                                       struct sk_entry *first)
+{
+       unsigned int this_len = FIO_SERVER_MAX_FRAGMENT_PDU - stream->avail_out;
+
+       *last_entry = fio_net_prep_cmd(FIO_NET_CMD_IOLOG, out_pdu, this_len,
+                                NULL, SK_F_VEC | SK_F_INLINE | SK_F_FREE);
+       flist_add_tail(&(*last_entry)->list, &first->next);
+
+}
+
 /*
- * Send a command with a separate PDU, not inlined in the command
+ * Deflates the next input given, creating as many new packets in the
+ * linked list as necessary.
  */
-static int fio_send_cmd_ext_pdu(int sk, uint16_t opcode, const void *buf,
-                               off_t size, uint64_t tag, uint32_t flags)
+static int __deflate_pdu_buffer(void *next_in, unsigned int next_sz, void **out_pdu,
+                               struct sk_entry **last_entry, z_stream *stream,
+                               struct sk_entry *first)
 {
-       struct fio_net_cmd cmd;
-       struct iovec iov[2];
+       int ret;
 
-       iov[0].iov_base = (void *) &cmd;
-       iov[0].iov_len = sizeof(cmd);
-       iov[1].iov_base = (void *) buf;
-       iov[1].iov_len = size;
+       stream->next_in = next_in;
+       stream->avail_in = next_sz;
+       do {
+               if (! stream->avail_out) {
 
-       __fio_init_net_cmd(&cmd, opcode, size, tag);
-       cmd.flags = __cpu_to_le32(flags);
-       fio_net_cmd_crc_pdu(&cmd, buf);
+                       __fio_net_prep_tail(stream, *out_pdu, last_entry, first);
+
+                       *out_pdu = malloc(FIO_SERVER_MAX_FRAGMENT_PDU);
+
+                       stream->avail_out = FIO_SERVER_MAX_FRAGMENT_PDU;
+                       stream->next_out = *out_pdu;
+               }
 
-       return fio_sendv_data(sk, iov, 2);
+               ret = deflate(stream, Z_BLOCK);
+
+               if (ret < 0) {
+                       free(*out_pdu);
+                       return 1;
+               }
+       } while (stream->avail_in);
+
+       return 0;
 }
 
-static int fio_send_iolog_gz(struct cmd_iolog_pdu *pdu, struct io_log *log)
+static int __fio_append_iolog_gz_hist(struct sk_entry *first, struct io_log *log,
+                                     struct io_logs *cur_log, z_stream *stream)
 {
-       int ret = 0;
-#ifdef CONFIG_ZLIB
-       z_stream stream;
+       struct sk_entry *entry;
        void *out_pdu;
+       int ret, i, j;
+       int sample_sz = log_entry_sz(log);
 
-       /*
-        * Dirty - since the log is potentially huge, compress it into
-        * FIO_SERVER_MAX_FRAGMENT_PDU chunks and let the receiving
-        * side defragment it.
-        */
        out_pdu = malloc(FIO_SERVER_MAX_FRAGMENT_PDU);
+       stream->avail_out = FIO_SERVER_MAX_FRAGMENT_PDU;
+       stream->next_out = out_pdu;
 
-       stream.zalloc = Z_NULL;
-       stream.zfree = Z_NULL;
-       stream.opaque = Z_NULL;
+       for (i = 0; i < cur_log->nr_samples; i++) {
+               struct io_sample *s;
+               struct io_u_plat_entry *cur_plat_entry, *prev_plat_entry;
+               uint64_t *cur_plat, *prev_plat;
 
-       if (deflateInit(&stream, Z_DEFAULT_COMPRESSION) != Z_OK) {
-               ret = 1;
-               goto err;
+               s = get_sample(log, cur_log, i);
+               ret = __deflate_pdu_buffer(s, sample_sz, &out_pdu, &entry, stream, first);
+               if (ret)
+                       return ret;
+
+               /* Do the subtraction on server side so that client doesn't have to
+                * reconstruct our linked list from packets.
+                */
+               cur_plat_entry  = s->data.plat_entry;
+               prev_plat_entry = flist_first_entry(&cur_plat_entry->list, struct io_u_plat_entry, list);
+               cur_plat  = cur_plat_entry->io_u_plat;
+               prev_plat = prev_plat_entry->io_u_plat;
+
+               for (j = 0; j < FIO_IO_U_PLAT_NR; j++) {
+                       cur_plat[j] -= prev_plat[j];
+               }
+
+               flist_del(&prev_plat_entry->list);
+               free(prev_plat_entry);
+
+               ret = __deflate_pdu_buffer(cur_plat_entry, sizeof(*cur_plat_entry),
+                                          &out_pdu, &entry, stream, first);
+
+               if (ret)
+                       return ret;
        }
 
-       stream.next_in = (void *) log->log;
-       stream.avail_in = log->nr_samples * log_entry_sz(log);
+       __fio_net_prep_tail(stream, out_pdu, &entry, first);
+
+       return 0;
+}
+
+static int __fio_append_iolog_gz(struct sk_entry *first, struct io_log *log,
+                                struct io_logs *cur_log, z_stream *stream)
+{
+       unsigned int this_len;
+       void *out_pdu;
+       int ret;
+
+       if (log->log_type == IO_LOG_TYPE_HIST)
+               return __fio_append_iolog_gz_hist(first, log, cur_log, stream);
+
+       stream->next_in = (void *) cur_log->log;
+       stream->avail_in = cur_log->nr_samples * log_entry_sz(log);
 
        do {
-               unsigned int this_len, flags = 0;
+               struct sk_entry *entry;
+
+               /*
+                * Dirty - since the log is potentially huge, compress it into
+                * FIO_SERVER_MAX_FRAGMENT_PDU chunks and let the receiving
+                * side defragment it.
+                */
+               out_pdu = malloc(FIO_SERVER_MAX_FRAGMENT_PDU);
+
+               stream->avail_out = FIO_SERVER_MAX_FRAGMENT_PDU;
+               stream->next_out = out_pdu;
+               ret = deflate(stream, Z_BLOCK);
+               /* may be Z_OK, or Z_STREAM_END */
+               if (ret < 0) {
+                       free(out_pdu);
+                       return 1;
+               }
 
+               this_len = FIO_SERVER_MAX_FRAGMENT_PDU - stream->avail_out;
+
+               entry = fio_net_prep_cmd(FIO_NET_CMD_IOLOG, out_pdu, this_len,
+                                        NULL, SK_F_VEC | SK_F_INLINE | SK_F_FREE);
+               flist_add_tail(&entry->list, &first->next);
+       } while (stream->avail_in);
+
+       return 0;
+}
+
+static int fio_append_iolog_gz(struct sk_entry *first, struct io_log *log)
+{
+       z_stream stream = {
+               .zalloc = Z_NULL,
+               .zfree  = Z_NULL,
+               .opaque = Z_NULL,
+       };
+       int ret = 0;
+
+       if (deflateInit(&stream, Z_DEFAULT_COMPRESSION) != Z_OK)
+               return 1;
+
+       while (!flist_empty(&log->io_logs)) {
+               struct io_logs *cur_log;
+
+               cur_log = flist_first_entry(&log->io_logs, struct io_logs, list);
+               flist_del_init(&cur_log->list);
+
+               ret = __fio_append_iolog_gz(first, log, cur_log, &stream);
+               if (ret)
+                       break;
+       }
+
+       ret = deflate(&stream, Z_FINISH);
+
+       while (ret != Z_STREAM_END) {
+               struct sk_entry *entry;
+               unsigned int this_len;
+               void *out_pdu;
+
+               out_pdu = malloc(FIO_SERVER_MAX_FRAGMENT_PDU);
                stream.avail_out = FIO_SERVER_MAX_FRAGMENT_PDU;
                stream.next_out = out_pdu;
+
                ret = deflate(&stream, Z_FINISH);
                /* may be Z_OK, or Z_STREAM_END */
-               if (ret < 0)
-                       goto err_zlib;
+               if (ret < 0) {
+                       free(out_pdu);
+                       break;
+               }
 
                this_len = FIO_SERVER_MAX_FRAGMENT_PDU - stream.avail_out;
 
-               if (stream.avail_in)
-                       flags = FIO_NET_CMD_F_MORE;
+               entry = fio_net_prep_cmd(FIO_NET_CMD_IOLOG, out_pdu, this_len,
+                                        NULL, SK_F_VEC | SK_F_INLINE | SK_F_FREE);
+               flist_add_tail(&entry->list, &first->next);
+       } while (ret != Z_STREAM_END);
 
-               ret = fio_send_cmd_ext_pdu(server_fd, FIO_NET_CMD_IOLOG,
-                                          out_pdu, this_len, 0, flags);
-               if (ret)
-                       goto err_zlib;
-       } while (stream.avail_in);
+       ret = deflateEnd(&stream);
+       if (ret == Z_OK)
+               return 0;
 
-err_zlib:
-       deflateEnd(&stream);
-err:
-       free(out_pdu);
+       return 1;
+}
+#else
+static int fio_append_iolog_gz(struct sk_entry *first, struct io_log *log)
+{
+       return 1;
+}
 #endif
-       return ret;
+
+static int fio_append_gz_chunks(struct sk_entry *first, struct io_log *log)
+{
+       struct sk_entry *entry;
+       struct flist_head *node;
+
+       pthread_mutex_lock(&log->chunk_lock);
+       flist_for_each(node, &log->chunk_list) {
+               struct iolog_compress *c;
+
+               c = flist_entry(node, struct iolog_compress, list);
+               entry = fio_net_prep_cmd(FIO_NET_CMD_IOLOG, c->buf, c->len,
+                                               NULL, SK_F_VEC | SK_F_INLINE);
+               flist_add_tail(&entry->list, &first->next);
+       }
+       pthread_mutex_unlock(&log->chunk_lock);
+
+       return 0;
+}
+
+static int fio_append_text_log(struct sk_entry *first, struct io_log *log)
+{
+       struct sk_entry *entry;
+
+       while (!flist_empty(&log->io_logs)) {
+               struct io_logs *cur_log;
+               size_t size;
+
+               cur_log = flist_first_entry(&log->io_logs, struct io_logs, list);
+               flist_del_init(&cur_log->list);
+
+               size = cur_log->nr_samples * log_entry_sz(log);
+
+               entry = fio_net_prep_cmd(FIO_NET_CMD_IOLOG, cur_log->log, size,
+                                               NULL, SK_F_VEC | SK_F_INLINE);
+               flist_add_tail(&entry->list, &first->next);
+       }
+
+       return 0;
 }
 
 int fio_send_iolog(struct thread_data *td, struct io_log *log, const char *name)
 {
-       struct cmd_iolog_pdu pdu;
-       int i, ret = 0;
+       struct cmd_iolog_pdu pdu = {
+               .nr_samples             = cpu_to_le64(iolog_nr_samples(log)),
+               .thread_number          = cpu_to_le32(td->thread_number),
+               .log_type               = cpu_to_le32(log->log_type),
+               .log_hist_coarseness    = cpu_to_le32(log->hist_coarseness),
+       };
+       struct sk_entry *first;
+       struct flist_head *entry;
+       int ret = 0;
 
-       pdu.nr_samples = cpu_to_le64(log->nr_samples);
-       pdu.thread_number = cpu_to_le32(td->thread_number);
-       pdu.log_type = cpu_to_le32(log->log_type);
-       pdu.compressed = cpu_to_le32(use_zlib);
+       if (!flist_empty(&log->chunk_list))
+               pdu.compressed = __cpu_to_le32(STORE_COMPRESSED);
+       else if (use_zlib)
+               pdu.compressed = __cpu_to_le32(XMIT_COMPRESSED);
+       else
+               pdu.compressed = 0;
 
        strncpy((char *) pdu.name, name, FIO_NET_NAME_MAX);
        pdu.name[FIO_NET_NAME_MAX - 1] = '\0';
 
-       for (i = 0; i < log->nr_samples; i++) {
-               struct io_sample *s = get_sample(log, i);
+       /*
+        * We can't do this for a pre-compressed log, but for that case,
+        * log->nr_samples is zero anyway.
+        */
+       flist_for_each(entry, &log->io_logs) {
+               struct io_logs *cur_log;
+               int i;
+
+               cur_log = flist_entry(entry, struct io_logs, list);
+
+               for (i = 0; i < cur_log->nr_samples; i++) {
+                       struct io_sample *s = get_sample(log, cur_log, i);
 
-               s->time         = cpu_to_le64(s->time);
-               s->val          = cpu_to_le64(s->val);
-               s->__ddir       = cpu_to_le32(s->__ddir);
-               s->bs           = cpu_to_le32(s->bs);
+                       s->time         = cpu_to_le64(s->time);
+                       s->data.val     = cpu_to_le64(s->data.val);
+                       s->__ddir       = cpu_to_le32(s->__ddir);
+                       s->bs           = cpu_to_le32(s->bs);
 
-               if (log->log_offset) {
-                       struct io_sample_offset *so = (void *) s;
+                       if (log->log_offset) {
+                               struct io_sample_offset *so = (void *) s;
 
-                       so->offset = cpu_to_le64(so->offset);
+                               so->offset = cpu_to_le64(so->offset);
+                       }
                }
        }
 
        /*
-        * Send header first, it's not compressed.
+        * Assemble header entry first
         */
-       ret = fio_send_cmd_ext_pdu(server_fd, FIO_NET_CMD_IOLOG, &pdu,
-                                       sizeof(pdu), 0, FIO_NET_CMD_F_MORE);
-       if (ret)
-               return ret;
+       first = fio_net_prep_cmd(FIO_NET_CMD_IOLOG, &pdu, sizeof(pdu), NULL, SK_F_VEC | SK_F_INLINE | SK_F_COPY);
 
        /*
-        * Now send actual log, compress if we can, otherwise just plain
+        * Now append actual log entries. If log compression was enabled on
+        * the job, just send out the compressed chunks directly. If we
+        * have a plain log, compress if we can, then send. Otherwise, send
+        * the plain text output.
         */
-       if (use_zlib)
-               return fio_send_iolog_gz(&pdu, log);
+       if (!flist_empty(&log->chunk_list))
+               ret = fio_append_gz_chunks(first, log);
+       else if (use_zlib)
+               ret = fio_append_iolog_gz(first, log);
+       else
+               ret = fio_append_text_log(first, log);
 
-       return fio_send_cmd_ext_pdu(server_fd, FIO_NET_CMD_IOLOG, log->log,
-                       log->nr_samples * log_entry_sz(log), 0, 0);
+       fio_net_queue_entry(first);
+       return ret;
 }
 
 void fio_server_send_add_job(struct thread_data *td)
 {
-       struct cmd_add_job_pdu pdu;
+       struct cmd_add_job_pdu pdu = {
+               .thread_number = cpu_to_le32(td->thread_number),
+               .groupid = cpu_to_le32(td->groupid),
+       };
 
-       memset(&pdu, 0, sizeof(pdu));
-       pdu.thread_number = cpu_to_le32(td->thread_number);
-       pdu.groupid = cpu_to_le32(td->groupid);
        convert_thread_options_to_net(&pdu.top, &td->o);
 
-       fio_net_send_cmd(server_fd, FIO_NET_CMD_ADD_JOB, &pdu, sizeof(pdu), NULL, NULL);
+       fio_net_queue_cmd(FIO_NET_CMD_ADD_JOB, &pdu, sizeof(pdu), NULL,
+                               SK_F_COPY);
 }
 
 void fio_server_send_start(struct thread_data *td)
 {
-       assert(server_fd != -1);
+       struct sk_out *sk_out = pthread_getspecific(sk_out_key);
 
-       fio_net_send_simple_cmd(server_fd, FIO_NET_CMD_SERVER_START, 0, NULL);
+       assert(sk_out->sk != -1);
+
+       fio_net_queue_cmd(FIO_NET_CMD_SERVER_START, NULL, 0, NULL, SK_F_SIMPLE);
 }
 
 int fio_server_get_verify_state(const char *name, int threadnumber,
@@ -1417,14 +2025,13 @@ int fio_server_get_verify_state(const char *name, int threadnumber,
        struct cmd_reply *rep;
        uint64_t tag;
        void *data;
+       int ret;
 
        dprint(FD_NET, "server: request verify state\n");
 
        rep = smalloc(sizeof(*rep));
-       if (!rep) {
-               log_err("fio: smalloc pool too small\n");
-               return 1;
-       }
+       if (!rep)
+               return ENOMEM;
 
        __fio_mutex_init(&rep->lock, FIO_MUTEX_LOCKED);
        rep->data = NULL;
@@ -1433,24 +2040,27 @@ int fio_server_get_verify_state(const char *name, int threadnumber,
        verify_state_gen_name((char *) out.path, sizeof(out.path), name, me,
                                threadnumber);
        tag = (uint64_t) (uintptr_t) rep;
-       fio_net_send_cmd(server_fd, FIO_NET_CMD_SENDFILE, &out, sizeof(out),
-                               &tag, NULL);
+       fio_net_queue_cmd(FIO_NET_CMD_SENDFILE, &out, sizeof(out), &tag,
+                               SK_F_COPY);
 
        /*
         * Wait for the backend to receive the reply
         */
-       if (fio_mutex_down_timeout(&rep->lock, 10)) {
+       if (fio_mutex_down_timeout(&rep->lock, 10000)) {
                log_err("fio: timed out waiting for reply\n");
+               ret = ETIMEDOUT;
                goto fail;
        }
 
        if (rep->error) {
-               log_err("fio: failure on receiving state file: %s\n", strerror(rep->error));
+               log_err("fio: failure on receiving state file %s: %s\n",
+                               out.path, strerror(rep->error));
+               ret = rep->error;
 fail:
                *datap = NULL;
                sfree(rep);
-               fio_net_send_quit(server_fd);
-               return 1;
+               fio_net_queue_quit();
+               return ret;
        }
 
        /*
@@ -1458,12 +2068,15 @@ fail:
         * the header, and the thread_io_list checksum
         */
        s = rep->data + sizeof(struct verify_state_hdr);
-       if (verify_state_hdr(rep->data, s))
+       if (verify_state_hdr(rep->data, s)) {
+               ret = EILSEQ;
                goto fail;
+       }
 
        /*
         * Don't need the header from now, copy just the thread_io_list
         */
+       ret = 0;
        rep->size -= sizeof(struct verify_state_hdr);
        data = malloc(rep->size);
        memcpy(data, s, rep->size);
@@ -1472,7 +2085,7 @@ fail:
        sfree(rep->data);
        __fio_mutex_remove(&rep->lock);
        sfree(rep);
-       return 0;
+       return ret;
 }
 
 static int fio_init_server_ip(void)
@@ -1495,16 +2108,15 @@ static int fio_init_server_ip(void)
 
        opt = 1;
        if (setsockopt(sk, SOL_SOCKET, SO_REUSEADDR, (void *)&opt, sizeof(opt)) < 0) {
-               log_err("fio: setsockopt: %s\n", strerror(errno));
+               log_err("fio: setsockopt(REUSEADDR): %s\n", strerror(errno));
                close(sk);
                return -1;
        }
 #ifdef SO_REUSEPORT
-       if (setsockopt(sk, SOL_SOCKET, SO_REUSEPORT, &opt, sizeof(opt)) < 0) {
-               log_err("fio: setsockopt: %s\n", strerror(errno));
-               close(sk);
-               return -1;
-       }
+       /*
+        * Not fatal if fails, so just ignore it if that happens
+        */
+       setsockopt(sk, SOL_SOCKET, SO_REUSEPORT, &opt, sizeof(opt));
 #endif
 
        if (use_ipv6) {
@@ -1606,7 +2218,7 @@ static int fio_init_server_connection(void)
 
        log_info("fio: server listening on %s\n", bind_str);
 
-       if (listen(sk, 0) < 0) {
+       if (listen(sk, 4) < 0) {
                log_err("fio: listen: %s\n", strerror(errno));
                close(sk);
                return -1;
@@ -1627,11 +2239,10 @@ int fio_server_parse_host(const char *host, int ipv6, struct in_addr *inp,
                ret = inet_pton(AF_INET, host, inp);
 
        if (ret != 1) {
-               struct addrinfo hints, *res;
-
-               memset(&hints, 0, sizeof(hints));
-               hints.ai_family = ipv6 ? AF_INET6 : AF_INET;
-               hints.ai_socktype = SOCK_STREAM;
+               struct addrinfo *res, hints = {
+                       .ai_family = ipv6 ? AF_INET6 : AF_INET,
+                       .ai_socktype = SOCK_STREAM,
+               };
 
                ret = getaddrinfo(host, NULL, &hints, &res);
                if (ret) {
@@ -1664,7 +2275,7 @@ int fio_server_parse_host(const char *host, int ipv6, struct in_addr *inp,
  * For local domain sockets:
  *     *ptr is the filename, *is_sock is 1.
  */
-int fio_server_parse_string(const char *str, char **ptr, int *is_sock,
+int fio_server_parse_string(const char *str, char **ptr, bool *is_sock,
                            int *port, struct in_addr *inp,
                            struct in6_addr *inp6, int *ipv6)
 {
@@ -1673,13 +2284,13 @@ int fio_server_parse_string(const char *str, char **ptr, int *is_sock,
        int lport = 0;
 
        *ptr = NULL;
-       *is_sock = 0;
+       *is_sock = false;
        *port = fio_net_port;
        *ipv6 = 0;
 
        if (!strncmp(str, "sock:", 5)) {
                *ptr = strdup(str + 5);
-               *is_sock = 1;
+               *is_sock = true;
 
                return 0;
        }
@@ -1758,7 +2369,8 @@ int fio_server_parse_string(const char *str, char **ptr, int *is_sock,
 static int fio_handle_server_arg(void)
 {
        int port = fio_net_port;
-       int is_sock, ret = 0;
+       bool is_sock;
+       int ret = 0;
 
        saddr_in.sin_addr.s_addr = htonl(INADDR_ANY);
 
@@ -1789,14 +2401,30 @@ static void sig_int(int sig)
 
 static void set_sig_handlers(void)
 {
-       struct sigaction act;
+       struct sigaction act = {
+               .sa_handler = sig_int,
+               .sa_flags = SA_RESTART,
+       };
 
-       memset(&act, 0, sizeof(act));
-       act.sa_handler = sig_int;
-       act.sa_flags = SA_RESTART;
        sigaction(SIGINT, &act, NULL);
 }
 
+void fio_server_destroy_sk_key(void)
+{
+       pthread_key_delete(sk_out_key);
+}
+
+int fio_server_create_sk_key(void)
+{
+       if (pthread_key_create(&sk_out_key, NULL)) {
+               log_err("fio: can't create sk_out backend key\n");
+               return 1;
+       }
+
+       pthread_setspecific(sk_out_key, NULL);
+       return 0;
+}
+
 static int fio_server(void)
 {
        int sk, ret;
@@ -1828,8 +2456,12 @@ static int fio_server(void)
 
 void fio_server_got_signal(int signal)
 {
+       struct sk_out *sk_out = pthread_getspecific(sk_out_key);
+
+       assert(sk_out);
+
        if (signal == SIGPIPE)
-               server_fd = -1;
+               sk_out->sk = -1;
        else {
                log_info("\nfio: terminating on signal %d\n", signal);
                exit_backend = 1;
@@ -1903,7 +2535,7 @@ int fio_start_server(char *pidfile)
 
        pid = fork();
        if (pid < 0) {
-               log_err("fio: failed server fork: %s", strerror(errno));
+               log_err("fio: failed server fork: %s\n", strerror(errno));
                free(pidfile);
                return -1;
        } else if (pid) {