X-Git-Url: https://git.kernel.dk/?p=fio.git;a=blobdiff_plain;f=io_u.c;h=77557dfdca12748f1db2249c05efc93a21b09f4b;hp=161c2cb388d01218628da8468c1fdeba105e40ed;hb=79591fa9555024aa9564656bbbb9d4c828a3e189;hpb=13af05ae2ece4a277a2f95fd622d1717af538c20

diff --git a/io_u.c b/io_u.c
index 161c2cb3..46d97319 100644
--- a/io_u.c
+++ b/io_u.c
@@ -10,28 +10,26 @@
 #include "verify.h"
 #include "trim.h"
 #include "lib/rand.h"
+#include "lib/axmap.h"
+#include "err.h"
+#include "lib/pow2.h"
+#include "minmax.h"
 
 struct io_completion_data {
 	int nr;				/* input */
-	int account;			/* input */
 
 	int error;			/* output */
-	unsigned long bytes_done[2];	/* output */
+	uint64_t bytes_done[DDIR_RWDIR_CNT];	/* output */
 	struct timeval time;		/* output */
 };
 
 /*
- * The ->file_map[] contains a map of blocks we have or have not done io
+ * The ->io_axmap contains a map of blocks we have or have not done io
  * to yet. Used to make sure we cover the entire range in a fair fashion.
  */
-static int random_map_free(struct fio_file *f, const unsigned long long block)
+static bool random_map_free(struct fio_file *f, const uint64_t block)
 {
-	unsigned int idx = RAND_MAP_IDX(f, block);
-	unsigned int bit = RAND_MAP_BIT(f, block);
-
-	dprint(FD_RANDOM, "free: b=%llu, idx=%u, bit=%u\n", block, idx, bit);
-
-	return (f->file_map[idx] & (1UL << bit)) == 0;
+	return !axmap_isset(f->io_axmap, block);
 }
 
 /*
@@ -41,74 +39,30 @@ static void mark_random_map(struct thread_data *td, struct io_u *io_u)
 {
 	unsigned int min_bs = td->o.rw_min_bs;
 	struct fio_file *f = io_u->file;
-	unsigned long long block;
-	unsigned int blocks, nr_blocks;
-	int busy_check;
+	unsigned int nr_blocks;
+	uint64_t block;
 
-	block = (io_u->offset - f->file_offset) / (unsigned long long) min_bs;
+	block = (io_u->offset - f->file_offset) / (uint64_t) min_bs;
 	nr_blocks = (io_u->buflen + min_bs - 1) / min_bs;
-	blocks = 0;
-	busy_check = !(io_u->flags & IO_U_F_BUSY_OK);
-
-	while (nr_blocks) {
-		unsigned int idx, bit;
-		unsigned long mask, this_blocks;
-
-		/*
-		 * If we have a mixed random workload, we may
-		 * encounter blocks we already did IO to.
-		 */
-		if (!busy_check) {
-			blocks = nr_blocks;
-			break;
-		}
-		if ((td->o.ddir_seq_nr == 1) && !random_map_free(f, block))
-			break;
-
-		idx = RAND_MAP_IDX(f, block);
-		bit = RAND_MAP_BIT(f, block);
-
-		fio_assert(td, idx < f->num_maps);
 
-		this_blocks = nr_blocks;
-		if (this_blocks + bit > BLOCKS_PER_MAP)
-			this_blocks = BLOCKS_PER_MAP - bit;
-
-		do {
-			if (this_blocks == BLOCKS_PER_MAP)
-				mask = -1UL;
-			else
-				mask = ((1UL << this_blocks) - 1) << bit;
-	
-			if (!(f->file_map[idx] & mask))
-				break;
+	if (!(io_u->flags & IO_U_F_BUSY_OK))
+		nr_blocks = axmap_set_nr(f->io_axmap, block, nr_blocks);
 
-			this_blocks--;
-		} while (this_blocks);
-
-		if (!this_blocks)
-			break;
-
-		f->file_map[idx] |= mask;
-		nr_blocks -= this_blocks;
-		blocks += this_blocks;
-		block += this_blocks;
-	}
-
-	if ((blocks * min_bs) < io_u->buflen)
-		io_u->buflen = blocks * min_bs;
+	if ((nr_blocks * min_bs) < io_u->buflen)
+		io_u->buflen = nr_blocks * min_bs;
 }
 
-static unsigned long long last_block(struct thread_data *td, struct fio_file *f,
-				     enum fio_ddir ddir)
+static uint64_t last_block(struct thread_data *td, struct fio_file *f,
+			   enum fio_ddir ddir)
 {
-	unsigned long long max_blocks;
-	unsigned long long max_size;
+	uint64_t max_blocks;
+	uint64_t max_size;
 
 	assert(ddir_rw(ddir));
 
 	/*
 	 * Hmm, should we make sure that ->io_size <= ->real_file_size?
+	 * -> not for now since there is code assuming it could go either.
 	 */
 	max_size = f->io_size;
 	if (max_size > f->real_file_size)
@@ -117,152 +71,330 @@ static unsigned long long last_block(struct thread_data *td, struct fio_file *f,
 	if (td->o.zone_range)
 		max_size = td->o.zone_range;
 
-	max_blocks = max_size / (unsigned long long) td->o.ba[ddir];
+	if (td->o.min_bs[ddir] > td->o.ba[ddir])
+		max_size -= td->o.min_bs[ddir] - td->o.ba[ddir];
+
+	max_blocks = max_size / (uint64_t) td->o.ba[ddir];
 	if (!max_blocks)
 		return 0;
 
 	return max_blocks;
 }
 
-/*
- * Return the next free block in the map.
- */
-static int get_next_free_block(struct thread_data *td, struct fio_file *f,
-			       enum fio_ddir ddir, unsigned long long *b)
+struct rand_off {
+	struct flist_head list;
+	uint64_t off;
+};
+
+static int __get_next_rand_offset(struct thread_data *td, struct fio_file *f,
+				  enum fio_ddir ddir, uint64_t *b,
+				  uint64_t lastb)
 {
-	unsigned long long block, min_bs = td->o.rw_min_bs, lastb;
-	int i;
+	uint64_t r;
 
-	lastb = last_block(td, f, ddir);
-	if (!lastb)
-		return 1;
+	if (td->o.random_generator == FIO_RAND_GEN_TAUSWORTHE ||
+	    td->o.random_generator == FIO_RAND_GEN_TAUSWORTHE64) {
 
-	i = f->last_free_lookup;
-	block = i * BLOCKS_PER_MAP;
-	while (block * min_bs < f->real_file_size &&
-		block * min_bs < f->io_size) {
-		if (f->file_map[i] != -1UL) {
-			block += ffz(f->file_map[i]);
-			if (block > lastb)
-				break;
-			f->last_free_lookup = i;
-			*b = block;
-			return 0;
-		}
+		r = __rand(&td->random_state);
+
+		dprint(FD_RANDOM, "off rand %llu\n", (unsigned long long) r);
+
+		*b = lastb * (r / (rand_max(&td->random_state) + 1.0));
+	} else {
+		uint64_t off = 0;
+
+		assert(fio_file_lfsr(f));
 
-		block += BLOCKS_PER_MAP;
-		i++;
+		if (lfsr_next(&f->lfsr, &off))
+			return 1;
+
+		*b = off;
 	}
 
-	dprint(FD_IO, "failed finding a free block\n");
-	return 1;
-}
+	/*
+	 * if we are not maintaining a random map, we are done.
+	 */
+	if (!file_randommap(td, f))
+		goto ret;
 
-static int get_next_rand_offset(struct thread_data *td, struct fio_file *f,
-				enum fio_ddir ddir, unsigned long long *b)
-{
-	unsigned long long rmax, r, lastb;
-	int loops = 5;
+	/*
+	 * calculate map offset and check if it's free
+	 */
+	if (random_map_free(f, *b))
+		goto ret;
 
-	lastb = last_block(td, f, ddir);
-	if (!lastb)
+	dprint(FD_RANDOM, "get_next_rand_offset: offset %llu busy\n",
+						(unsigned long long) *b);
+
+	*b = axmap_next_free(f->io_axmap, *b);
+	if (*b == (uint64_t) -1ULL)
 		return 1;
+ret:
+	return 0;
+}
 
-	if (f->failed_rands >= 200)
-		goto ffz;
+static int __get_next_rand_offset_zipf(struct thread_data *td,
+				       struct fio_file *f, enum fio_ddir ddir,
+				       uint64_t *b)
+{
+	*b = zipf_next(&f->zipf);
+	return 0;
+}
 
-	rmax = td->o.use_os_rand ? OS_RAND_MAX : FRAND_MAX;
-	do {
-		if (td->o.use_os_rand)
-			r = os_random_long(&td->random_state);
-		else
-			r = __rand(&td->__random_state);
+static int __get_next_rand_offset_pareto(struct thread_data *td,
+					 struct fio_file *f, enum fio_ddir ddir,
+					 uint64_t *b)
+{
+	*b = pareto_next(&f->zipf);
+	return 0;
+}
 
-		*b = (lastb - 1) * (r / ((unsigned long long) rmax + 1.0));
+static int __get_next_rand_offset_gauss(struct thread_data *td,
+					struct fio_file *f, enum fio_ddir ddir,
+					uint64_t *b)
+{
+	*b = gauss_next(&f->gauss);
+	return 0;
+}
 
-		dprint(FD_RANDOM, "off rand %llu\n", r);
+static int __get_next_rand_offset_zoned(struct thread_data *td,
+					struct fio_file *f, enum fio_ddir ddir,
+					uint64_t *b)
+{
+	unsigned int v, send, stotal;
+	uint64_t offset, lastb;
+	static int warned;
+	struct zone_split_index *zsi;
 
+	lastb = last_block(td, f, ddir);
+	if (!lastb)
+		return 1;
 
-		/*
-		 * if we are not maintaining a random map, we are done.
-		 */
-		if (!file_randommap(td, f))
-			goto ret_good;
+	if (!td->o.zone_split_nr[ddir]) {
+bail:
+		return __get_next_rand_offset(td, f, ddir, b, lastb);
+	}
 
-		/*
-		 * calculate map offset and check if it's free
-		 */
-		if (random_map_free(f, *b))
-			goto ret_good;
+	/*
+	 * Generate a value, v, between 1 and 100, both inclusive
+	 */
+	v = rand32_between(&td->zone_state, 1, 100);
 
-		dprint(FD_RANDOM, "get_next_rand_offset: offset %llu busy\n",
-									*b);
-	} while (--loops);
+	zsi = &td->zone_state_index[ddir][v - 1];
+	stotal = zsi->size_perc_prev;
+	send = zsi->size_perc;
 
-	if (!f->failed_rands++)
-		f->last_free_lookup = 0;
+	/*
+	 * Should never happen
+	 */
+	if (send == -1U) {
+		if (!warned) {
+			log_err("fio: bug in zoned generation\n");
+			warned = 1;
+		}
+		goto bail;
+	}
 
 	/*
-	 * we get here, if we didn't suceed in looking up a block. generate
-	 * a random start offset into the filemap, and find the first free
-	 * block from there.
+	 * 'send' is some percentage below or equal to 100 that
+	 * marks the end of the current IO range. 'stotal' marks
+	 * the start, in percent.
 	 */
-	loops = 10;
-	do {
-		f->last_free_lookup = (f->num_maps - 1) *
-					(r / ((unsigned long long) rmax + 1.0));
-		if (!get_next_free_block(td, f, ddir, b))
-			goto ret;
+	if (stotal)
+		offset = stotal * lastb / 100ULL;
+	else
+		offset = 0;
 
-		if (td->o.use_os_rand)
-			r = os_random_long(&td->random_state);
-		else
-			r = __rand(&td->__random_state);
-	} while (--loops);
+	lastb = lastb * (send - stotal) / 100ULL;
 
 	/*
-	 * that didn't work either, try exhaustive search from the start
+	 * Generate index from 0..send-of-lastb
 	 */
-	f->last_free_lookup = 0;
-ffz:
-	if (!get_next_free_block(td, f, ddir, b))
-		return 0;
-	f->last_free_lookup = 0;
-	return get_next_free_block(td, f, ddir, b);
-ret_good:
-	f->failed_rands = 0;
-ret:
+	if (__get_next_rand_offset(td, f, ddir, b, lastb) == 1)
+		return 1;
+
+	/*
+	 * Add our start offset, if any
+	 */
+	if (offset)
+		*b += offset;
+
 	return 0;
 }
 
+static int flist_cmp(void *data, struct flist_head *a, struct flist_head *b)
+{
+	struct rand_off *r1 = flist_entry(a, struct rand_off, list);
+	struct rand_off *r2 = flist_entry(b, struct rand_off, list);
+
+	return r1->off - r2->off;
+}
+
+static int get_off_from_method(struct thread_data *td, struct fio_file *f,
+			       enum fio_ddir ddir, uint64_t *b)
+{
+	if (td->o.random_distribution == FIO_RAND_DIST_RANDOM) {
+		uint64_t lastb;
+
+		lastb = last_block(td, f, ddir);
+		if (!lastb)
+			return 1;
+
+		return __get_next_rand_offset(td, f, ddir, b, lastb);
+	} else if (td->o.random_distribution == FIO_RAND_DIST_ZIPF)
+		return __get_next_rand_offset_zipf(td, f, ddir, b);
+	else if (td->o.random_distribution == FIO_RAND_DIST_PARETO)
+		return __get_next_rand_offset_pareto(td, f, ddir, b);
+	else if (td->o.random_distribution == FIO_RAND_DIST_GAUSS)
+		return __get_next_rand_offset_gauss(td, f, ddir, b);
+	else if (td->o.random_distribution == FIO_RAND_DIST_ZONED)
+		return __get_next_rand_offset_zoned(td, f, ddir, b);
+
+	log_err("fio: unknown random distribution: %d\n", td->o.random_distribution);
+	return 1;
+}
+
+/*
+ * Sort the reads for a verify phase in batches of verifysort_nr, if
+ * specified.
+ */
+static inline bool should_sort_io(struct thread_data *td)
+{
+	if (!td->o.verifysort_nr || !td->o.do_verify)
+		return false;
+	if (!td_random(td))
+		return false;
+	if (td->runstate != TD_VERIFYING)
+		return false;
+	if (td->o.random_generator == FIO_RAND_GEN_TAUSWORTHE ||
+	    td->o.random_generator == FIO_RAND_GEN_TAUSWORTHE64)
+		return false;
+
+	return true;
+}
+
+static bool should_do_random(struct thread_data *td, enum fio_ddir ddir)
+{
+	unsigned int v;
+
+	if (td->o.perc_rand[ddir] == 100)
+		return true;
+
+	v = rand32_between(&td->seq_rand_state[ddir], 1, 100);
+
+	return v <= td->o.perc_rand[ddir];
+}
+
+static int get_next_rand_offset(struct thread_data *td, struct fio_file *f,
+				enum fio_ddir ddir, uint64_t *b)
+{
+	struct rand_off *r;
+	int i, ret = 1;
+
+	if (!should_sort_io(td))
+		return get_off_from_method(td, f, ddir, b);
+
+	if (!flist_empty(&td->next_rand_list)) {
+fetch:
+		r = flist_first_entry(&td->next_rand_list, struct rand_off, list);
+		flist_del(&r->list);
+		*b = r->off;
+		free(r);
+		return 0;
+	}
+
+	for (i = 0; i < td->o.verifysort_nr; i++) {
+		r = malloc(sizeof(*r));
+
+		ret = get_off_from_method(td, f, ddir, &r->off);
+		if (ret) {
+			free(r);
+			break;
+		}
+
+		flist_add(&r->list, &td->next_rand_list);
+	}
+
+	if (ret && !i)
+		return ret;
+
+	assert(!flist_empty(&td->next_rand_list));
+	flist_sort(NULL, &td->next_rand_list, flist_cmp);
+	goto fetch;
+}
+
 static int get_next_rand_block(struct thread_data *td, struct fio_file *f,
-			       enum fio_ddir ddir, unsigned long long *b)
+			       enum fio_ddir ddir, uint64_t *b)
 {
-	if (get_next_rand_offset(td, f, ddir, b)) {
-		dprint(FD_IO, "%s: rand offset failed, last=%llu, size=%llu\n",
-				f->file_name, f->last_pos, f->real_file_size);
-		return 1;
+	if (!get_next_rand_offset(td, f, ddir, b))
+		return 0;
+
+	if (td->o.time_based ||
+	    (td->o.file_service_type & __FIO_FSERVICE_NONUNIFORM)) {
+		fio_file_reset(td, f);
+		if (!get_next_rand_offset(td, f, ddir, b))
+			return 0;
 	}
 
-	return 0;
+	dprint(FD_IO, "%s: rand offset failed, last=%llu, size=%llu\n",
+			f->file_name, (unsigned long long) f->last_pos[ddir],
+			(unsigned long long) f->real_file_size);
+	return 1;
 }
 
-static int get_next_seq_block(struct thread_data *td, struct fio_file *f,
-			      enum fio_ddir ddir, unsigned long long *b)
+static int get_next_seq_offset(struct thread_data *td, struct fio_file *f,
+			       enum fio_ddir ddir, uint64_t *offset)
 {
+	struct thread_options *o = &td->o;
+
 	assert(ddir_rw(ddir));
 
-	if (f->last_pos < f->real_file_size) {
-		unsigned long long pos;
+	if (f->last_pos[ddir] >= f->io_size + get_start_offset(td, f) &&
+	    o->time_based) {
+		struct thread_options *o = &td->o;
+		uint64_t io_size = f->io_size + (f->io_size % o->min_bs[ddir]);
 
-		if (f->last_pos == f->file_offset && td->o.ddir_seq_add < 0)
-			f->last_pos = f->real_file_size;
+		if (io_size > f->last_pos[ddir])
+			f->last_pos[ddir] = 0;
+		else
+			f->last_pos[ddir] = f->last_pos[ddir] - io_size;
+	}
 
-		pos = f->last_pos - f->file_offset;
-		if (pos)
-			pos += td->o.ddir_seq_add;
+	if (f->last_pos[ddir] < f->real_file_size) {
+		uint64_t pos;
 
-		*b = pos / td->o.min_bs[ddir];
+		if (f->last_pos[ddir] == f->file_offset && o->ddir_seq_add < 0) {
+			if (f->real_file_size > f->io_size)
+				f->last_pos[ddir] = f->io_size;
+			else
+				f->last_pos[ddir] = f->real_file_size;
+		}
+
+		pos = f->last_pos[ddir] - f->file_offset;
+		if (pos && o->ddir_seq_add) {
+			pos += o->ddir_seq_add;
+
+			/*
+			 * If we reach beyond the end of the file
+			 * with holed IO, wrap around to the
+			 * beginning again. If we're doing backwards IO,
+			 * wrap to the end.
+			 */
+			if (pos >= f->real_file_size) {
+				if (o->ddir_seq_add > 0)
+					pos = f->file_offset;
+				else {
+					if (f->real_file_size > f->io_size)
+						pos = f->io_size;
+					else
+						pos = f->real_file_size;
+
+					pos += o->ddir_seq_add;
+				}
+			}
+		}
+
+		*offset = pos;
 		return 0;
 	}
 
@@ -270,38 +402,66 @@ static int get_next_seq_block(struct thread_data *td, struct fio_file *f,
 }
 
 static int get_next_block(struct thread_data *td, struct io_u *io_u,
-			  enum fio_ddir ddir, int rw_seq, unsigned long long *b)
+			  enum fio_ddir ddir, int rw_seq,
+			  unsigned int *is_random)
 {
 	struct fio_file *f = io_u->file;
+	uint64_t b, offset;
 	int ret;
 
 	assert(ddir_rw(ddir));
 
+	b = offset = -1ULL;
+
 	if (rw_seq) {
-		if (td_random(td))
-			ret = get_next_rand_block(td, f, ddir, b);
-		else
-			ret = get_next_seq_block(td, f, ddir, b);
+		if (td_random(td)) {
+			if (should_do_random(td, ddir)) {
+				ret = get_next_rand_block(td, f, ddir, &b);
+				*is_random = 1;
+			} else {
+				*is_random = 0;
+				io_u_set(td, io_u, IO_U_F_BUSY_OK);
+				ret = get_next_seq_offset(td, f, ddir, &offset);
+				if (ret)
+					ret = get_next_rand_block(td, f, ddir, &b);
+			}
+		} else {
+			*is_random = 0;
+			ret = get_next_seq_offset(td, f, ddir, &offset);
+		}
 	} else {
-		io_u->flags |= IO_U_F_BUSY_OK;
+		io_u_set(td, io_u, IO_U_F_BUSY_OK);
+		*is_random = 0;
 
 		if (td->o.rw_seq == RW_SEQ_SEQ) {
-			ret = get_next_seq_block(td, f, ddir, b);
-			if (ret)
-				ret = get_next_rand_block(td, f, ddir, b);
+			ret = get_next_seq_offset(td, f, ddir, &offset);
+			if (ret) {
+				ret = get_next_rand_block(td, f, ddir, &b);
+				*is_random = 0;
+			}
 		} else if (td->o.rw_seq == RW_SEQ_IDENT) {
-			if (f->last_start != -1ULL)
-				*b = (f->last_start - f->file_offset)
-					/ td->o.min_bs[ddir];
+			if (f->last_start[ddir] != -1ULL)
+				offset = f->last_start[ddir] - f->file_offset;
 			else
-				*b = 0;
+				offset = 0;
 			ret = 0;
 		} else {
 			log_err("fio: unknown rw_seq=%d\n", td->o.rw_seq);
 			ret = 1;
 		}
 	}
-	
+
+	if (!ret) {
+		if (offset != -1ULL)
+			io_u->offset = offset;
+		else if (b != -1ULL)
+			io_u->offset = b * td->o.ba[ddir];
+		else {
+			log_err("fio: bug in offset generation: offset=%llu, b=%llu\n", (unsigned long long) offset, (unsigned long long) b);
+			ret = 1;
+		}
+	}
+
 	return ret;
 }
 
@@ -310,10 +470,10 @@ static int get_next_block(struct thread_data *td, struct io_u *io_u,
  * until we find a free one. For sequential io, just return the end of
  * the last io issued.
  */
-static int __get_next_offset(struct thread_data *td, struct io_u *io_u)
+static int __get_next_offset(struct thread_data *td, struct io_u *io_u,
+			     unsigned int *is_random)
 {
 	struct fio_file *f = io_u->file;
-	unsigned long long b;
 	enum fio_ddir ddir = io_u->ddir;
 	int rw_seq_hit = 0;
 
@@ -324,53 +484,61 @@ static int __get_next_offset(struct thread_data *td, struct io_u *io_u)
 		td->ddir_seq_nr = td->o.ddir_seq_nr;
 	}
 
-	if (get_next_block(td, io_u, ddir, rw_seq_hit, &b))
+	if (get_next_block(td, io_u, ddir, rw_seq_hit, is_random))
 		return 1;
 
-	io_u->offset = b * td->o.ba[ddir];
 	if (io_u->offset >= f->io_size) {
 		dprint(FD_IO, "get_next_offset: offset %llu >= io_size %llu\n",
-					io_u->offset, f->io_size);
+					(unsigned long long) io_u->offset,
+					(unsigned long long) f->io_size);
 		return 1;
 	}
 
 	io_u->offset += f->file_offset;
 	if (io_u->offset >= f->real_file_size) {
 		dprint(FD_IO, "get_next_offset: offset %llu >= size %llu\n",
-					io_u->offset, f->real_file_size);
+					(unsigned long long) io_u->offset,
+					(unsigned long long) f->real_file_size);
 		return 1;
 	}
 
 	return 0;
 }
 
-static int get_next_offset(struct thread_data *td, struct io_u *io_u)
+static int get_next_offset(struct thread_data *td, struct io_u *io_u,
+			   unsigned int *is_random)
 {
-	struct prof_io_ops *ops = &td->prof_io_ops;
+	if (td->flags & TD_F_PROFILE_OPS) {
+		struct prof_io_ops *ops = &td->prof_io_ops;
 
-	if (ops->fill_io_u_off)
-		return ops->fill_io_u_off(td, io_u);
+		if (ops->fill_io_u_off)
+			return ops->fill_io_u_off(td, io_u, is_random);
+	}
 
-	return __get_next_offset(td, io_u);
+	return __get_next_offset(td, io_u, is_random);
 }
 
-static inline int io_u_fits(struct thread_data *td, struct io_u *io_u,
-			    unsigned int buflen)
+static inline bool io_u_fits(struct thread_data *td, struct io_u *io_u,
+			     unsigned int buflen)
 {
 	struct fio_file *f = io_u->file;
 
-	return io_u->offset + buflen <= f->io_size + td->o.start_offset;
+	return io_u->offset + buflen <= f->io_size + get_start_offset(td, f);
 }
 
-static unsigned int __get_next_buflen(struct thread_data *td, struct io_u *io_u)
+static unsigned int __get_next_buflen(struct thread_data *td, struct io_u *io_u,
+				      unsigned int is_random)
 {
-	const int ddir = io_u->ddir;
-	unsigned int uninitialized_var(buflen);
+	int ddir = io_u->ddir;
+	unsigned int buflen = 0;
 	unsigned int minbs, maxbs;
-	unsigned long r, rand_max;
+	uint64_t frand_max, r;
 
 	assert(ddir_rw(ddir));
 
+	if (td->o.bs_is_seq_rand)
+		ddir = is_random ? DDIR_WRITE: DDIR_READ;
+
 	minbs = td->o.min_bs[ddir];
 	maxbs = td->o.max_bs[ddir];
 
@@ -383,24 +551,17 @@ static unsigned int __get_next_buflen(struct thread_data *td, struct io_u *io_u)
 	if (!io_u_fits(td, io_u, minbs))
 		return 0;
 
-	if (td->o.use_os_rand)
-		rand_max = OS_RAND_MAX;
-	else
-		rand_max = FRAND_MAX;
-
+	frand_max = rand_max(&td->bsrange_state);
 	do {
-		if (td->o.use_os_rand)
-			r = os_random_long(&td->bsrange_state);
-		else
-			r = __rand(&td->__bsrange_state);
+		r = __rand(&td->bsrange_state);
 
 		if (!td->o.bssplit_nr[ddir]) {
 			buflen = 1 + (unsigned int) ((double) maxbs *
-					(r / (rand_max + 1.0)));
+					(r / (frand_max + 1.0)));
 			if (buflen < minbs)
 				buflen = minbs;
 		} else {
-			long perc = 0;
+			long long perc = 0;
 			unsigned int i;
 
 			for (i = 0; i < td->o.bssplit_nr[ddir]; i++) {
@@ -408,28 +569,33 @@ static unsigned int __get_next_buflen(struct thread_data *td, struct io_u *io_u)
 
 				buflen = bsp->bs;
 				perc += bsp->perc;
-				if ((r <= ((rand_max / 100L) * perc)) &&
+				if (!perc)
+					break;
+				if ((r / perc <= frand_max / 100ULL) &&
 				    io_u_fits(td, io_u, buflen))
 					break;
 			}
 		}
 
 		if (!td->o.bs_unaligned && is_power_of_2(minbs))
-			buflen = (buflen + minbs - 1) & ~(minbs - 1);
+			buflen &= ~(minbs - 1);
 
 	} while (!io_u_fits(td, io_u, buflen));
 
 	return buflen;
 }
 
-static unsigned int get_next_buflen(struct thread_data *td, struct io_u *io_u)
+static unsigned int get_next_buflen(struct thread_data *td, struct io_u *io_u,
+				    unsigned int is_random)
 {
-	struct prof_io_ops *ops = &td->prof_io_ops;
+	if (td->flags & TD_F_PROFILE_OPS) {
+		struct prof_io_ops *ops = &td->prof_io_ops;
 
-	if (ops->fill_io_u_size)
-		return ops->fill_io_u_size(td, io_u);
+		if (ops->fill_io_u_size)
+			return ops->fill_io_u_size(td, io_u, is_random);
+	}
 
-	return __get_next_buflen(td, io_u);
+	return __get_next_buflen(td, io_u, is_random);
 }
 
 static void set_rwmix_bytes(struct thread_data *td)
@@ -448,15 +614,8 @@ static void set_rwmix_bytes(struct thread_data *td)
 static inline enum fio_ddir get_rand_ddir(struct thread_data *td)
 {
 	unsigned int v;
-	unsigned long r;
 
-	if (td->o.use_os_rand) {
-		r = os_random_long(&td->rwmix_state);
-		v = 1 + (int) (100.0 * (r / (OS_RAND_MAX + 1.0)));
-	} else {
-		r = __rand(&td->__rwmix_state);
-		v = 1 + (int) (100.0 * (r / (FRAND_MAX + 1.0)));
-	}
+	v = rand32_between(&td->rwmix_state, 1, 100);
 
 	if (v <= td->o.rwmix[DDIR_READ])
 		return DDIR_READ;
@@ -464,66 +623,83 @@ static inline enum fio_ddir get_rand_ddir(struct thread_data *td)
 	return DDIR_WRITE;
 }
 
+int io_u_quiesce(struct thread_data *td)
+{
+	int completed = 0;
+
+	/*
+	 * We are going to sleep, ensure that we flush anything pending as
+	 * not to skew our latency numbers.
+	 *
+	 * Changed to only monitor 'in flight' requests here instead of the
+	 * td->cur_depth, b/c td->cur_depth does not accurately represent
+	 * io's that have been actually submitted to an async engine,
+	 * and cur_depth is meaningless for sync engines.
+	 */
+	if (td->io_u_queued || td->cur_depth) {
+		int fio_unused ret;
+
+		ret = td_io_commit(td);
+	}
+
+	while (td->io_u_in_flight) {
+		int fio_unused ret;
+
+		ret = io_u_queued_complete(td, 1);
+		if (ret > 0)
+			completed += ret;
+	}
+
+	if (td->flags & TD_F_REGROW_LOGS)
+		regrow_logs(td);
+
+	return completed;
+}
+
 static enum fio_ddir rate_ddir(struct thread_data *td, enum fio_ddir ddir)
 {
 	enum fio_ddir odir = ddir ^ 1;
-	struct timeval t;
 	long usec;
+	uint64_t now;
 
 	assert(ddir_rw(ddir));
+	now = utime_since_now(&td->start);
 
-	if (td->rate_pending_usleep[ddir] <= 0)
+	/*
+	 * if rate_next_io_time is in the past, need to catch up to rate
+	 */
+	if (td->rate_next_io_time[ddir] <= now)
 		return ddir;
 
 	/*
-	 * We have too much pending sleep in this direction. See if we
+	 * We are ahead of rate in this direction. See if we
 	 * should switch.
 	 */
-	if (td_rw(td)) {
+	if (td_rw(td) && td->o.rwmix[odir]) {
 		/*
-		 * Other direction does not have too much pending, switch
+		 * Other direction is behind rate, switch
 		 */
-		if (td->rate_pending_usleep[odir] < 100000)
+		if (td->rate_next_io_time[odir] <= now)
 			return odir;
 
 		/*
-		 * Both directions have pending sleep. Sleep the minimum time
-		 * and deduct from both.
+		 * Both directions are ahead of rate. sleep the min
+		 * switch if necissary
 		 */
-		if (td->rate_pending_usleep[ddir] <=
-			td->rate_pending_usleep[odir]) {
-			usec = td->rate_pending_usleep[ddir];
+		if (td->rate_next_io_time[ddir] <=
+			td->rate_next_io_time[odir]) {
+			usec = td->rate_next_io_time[ddir] - now;
 		} else {
-			usec = td->rate_pending_usleep[odir];
+			usec = td->rate_next_io_time[odir] - now;
 			ddir = odir;
 		}
 	} else
-		usec = td->rate_pending_usleep[ddir];
-
-	/*
-	 * We are going to sleep, ensure that we flush anything pending as
-	 * not to skew our latency numbers.
-	 *
-	 * Changed to only monitor 'in flight' requests here instead of the
-	 * td->cur_depth, b/c td->cur_depth does not accurately represent
-	 * io's that have been actually submitted to an async engine,
-	 * and cur_depth is meaningless for sync engines.
-	 */
-	if (td->io_u_in_flight) {
-		int fio_unused ret;
-
-		ret = io_u_queued_complete(td, td->io_u_in_flight, NULL);
-	}
+		usec = td->rate_next_io_time[ddir] - now;
 
-	fio_gettime(&t, NULL);
-	usec_sleep(td, usec);
-	usec = utime_since_now(&t);
+	if (td->o.io_submit_mode == IO_MODE_INLINE)
+		io_u_quiesce(td);
 
-	td->rate_pending_usleep[ddir] -= usec;
-
-	odir = ddir ^ 1;
-	if (td_rw(td) && __should_check_rate(td, odir))
-		td->rate_pending_usleep[odir] -= usec;
+	usec = usec_sleep(td, usec);
 
 	return ddir;
 }
@@ -581,8 +757,12 @@ static enum fio_ddir get_rw_ddir(struct thread_data *td)
 		ddir = td->rwmix_ddir;
 	} else if (td_read(td))
 		ddir = DDIR_READ;
-	else
+	else if (td_write(td))
 		ddir = DDIR_WRITE;
+	else if (td_trim(td))
+		ddir = DDIR_TRIM;
+	else
+		ddir = DDIR_INVAL;
 
 	td->rwmix_ddir = rate_ddir(td, ddir);
 	return td->rwmix_ddir;
@@ -590,18 +770,28 @@ static enum fio_ddir get_rw_ddir(struct thread_data *td)
 
 static void set_rw_ddir(struct thread_data *td, struct io_u *io_u)
 {
-	io_u->ddir = get_rw_ddir(td);
+	enum fio_ddir ddir = get_rw_ddir(td);
 
-	if (io_u->ddir == DDIR_WRITE && (td->io_ops->flags & FIO_BARRIER) &&
+	if (td_trimwrite(td)) {
+		struct fio_file *f = io_u->file;
+		if (f->last_pos[DDIR_WRITE] == f->last_pos[DDIR_TRIM])
+			ddir = DDIR_TRIM;
+		else
+			ddir = DDIR_WRITE;
+	}
+
+	io_u->ddir = io_u->acct_ddir = ddir;
+
+	if (io_u->ddir == DDIR_WRITE && td_ioengine_flagged(td, FIO_BARRIER) &&
 	    td->o.barrier_blocks &&
 	   !(td->io_issues[DDIR_WRITE] % td->o.barrier_blocks) &&
 	     td->io_issues[DDIR_WRITE])
-		io_u->flags |= IO_U_F_BARRIER;
+		io_u_set(td, io_u, IO_U_F_BARRIER);
 }
 
 void put_file_log(struct thread_data *td, struct fio_file *f)
 {
-	int ret = put_file(td, f);
+	unsigned int ret = put_file(td, f);
 
 	if (ret)
 		td_verror(td, ret, "file close");
@@ -609,52 +799,65 @@ void put_file_log(struct thread_data *td, struct fio_file *f)
 
 void put_io_u(struct thread_data *td, struct io_u *io_u)
 {
+	if (td->parent)
+		td = td->parent;
+
 	td_io_u_lock(td);
 
-	if (io_u->file && !(io_u->flags & IO_U_F_FREE_DEF))
+	if (io_u->file && !(io_u->flags & IO_U_F_NO_FILE_PUT))
 		put_file_log(td, io_u->file);
+
 	io_u->file = NULL;
-	io_u->flags &= ~IO_U_F_FREE_DEF;
-	io_u->flags |= IO_U_F_FREE;
+	io_u_set(td, io_u, IO_U_F_FREE);
 
-	if (io_u->flags & IO_U_F_IN_CUR_DEPTH)
+	if (io_u->flags & IO_U_F_IN_CUR_DEPTH) {
 		td->cur_depth--;
-	flist_del_init(&io_u->list);
-	flist_add(&io_u->list, &td->io_u_freelist);
+		assert(!(td->flags & TD_F_CHILD));
+	}
+	io_u_qpush(&td->io_u_freelist, io_u);
 	td_io_u_unlock(td);
 	td_io_u_free_notify(td);
 }
 
 void clear_io_u(struct thread_data *td, struct io_u *io_u)
 {
-	io_u->flags &= ~IO_U_F_FLIGHT;
+	io_u_clear(td, io_u, IO_U_F_FLIGHT);
 	put_io_u(td, io_u);
 }
 
 void requeue_io_u(struct thread_data *td, struct io_u **io_u)
 {
 	struct io_u *__io_u = *io_u;
+	enum fio_ddir ddir = acct_ddir(__io_u);
 
 	dprint(FD_IO, "requeue %p\n", __io_u);
 
+	if (td->parent)
+		td = td->parent;
+
 	td_io_u_lock(td);
 
-	__io_u->flags |= IO_U_F_FREE;
-	if ((__io_u->flags & IO_U_F_FLIGHT) && ddir_rw(__io_u->ddir))
-		td->io_issues[__io_u->ddir]--;
+	io_u_set(td, __io_u, IO_U_F_FREE);
+	if ((__io_u->flags & IO_U_F_FLIGHT) && ddir_rw(ddir))
+		td->io_issues[ddir]--;
 
-	__io_u->flags &= ~IO_U_F_FLIGHT;
-	if (__io_u->flags & IO_U_F_IN_CUR_DEPTH)
+	io_u_clear(td, __io_u, IO_U_F_FLIGHT);
+	if (__io_u->flags & IO_U_F_IN_CUR_DEPTH) {
 		td->cur_depth--;
-	flist_del(&__io_u->list);
-	flist_add_tail(&__io_u->list, &td->io_u_requeues);
+		assert(!(td->flags & TD_F_CHILD));
+	}
+
+	io_u_rpush(&td->io_u_requeues, __io_u);
 	td_io_u_unlock(td);
+	td_io_u_free_notify(td);
 	*io_u = NULL;
 }
 
 static int fill_io_u(struct thread_data *td, struct io_u *io_u)
 {
-	if (td->io_ops->flags & FIO_NOIO)
+	unsigned int is_random;
+
+	if (td_ioengine_flagged(td, FIO_NOIO))
 		goto out;
 
 	set_rw_ddir(td, io_u);
@@ -669,9 +872,17 @@ static int fill_io_u(struct thread_data *td, struct io_u *io_u)
 	 * See if it's time to switch to a new zone
 	 */
 	if (td->zone_bytes >= td->o.zone_size && td->o.zone_skip) {
+		struct fio_file *f = io_u->file;
+
 		td->zone_bytes = 0;
-		io_u->file->file_offset += td->o.zone_range + td->o.zone_skip;
-		io_u->file->last_pos = io_u->file->file_offset;
+		f->file_offset += td->o.zone_range + td->o.zone_skip;
+
+		/*
+		 * Wrap from the beginning, if we exceed the file size
+		 */
+		if (f->file_offset >= f->real_file_size)
+			f->file_offset = f->real_file_size - f->file_offset;
+		f->last_pos[io_u->ddir] = f->file_offset;
 		td->io_skip_bytes += td->o.zone_skip;
 	}
 
@@ -679,12 +890,12 @@ static int fill_io_u(struct thread_data *td, struct io_u *io_u)
 	 * No log, let the seq/rand engine retrieve the next buflen and
 	 * position.
 	 */
-	if (get_next_offset(td, io_u)) {
+	if (get_next_offset(td, io_u, &is_random)) {
 		dprint(FD_IO, "io_u %p, failed getting offset\n", io_u);
 		return 1;
 	}
 
-	io_u->buflen = get_next_buflen(td, io_u);
+	io_u->buflen = get_next_buflen(td, io_u, is_random);
 	if (!io_u->buflen) {
 		dprint(FD_IO, "io_u %p, failed getting buflen\n", io_u);
 		return 1;
@@ -692,8 +903,9 @@ static int fill_io_u(struct thread_data *td, struct io_u *io_u)
 
 	if (io_u->offset + io_u->buflen > io_u->file->real_file_size) {
 		dprint(FD_IO, "io_u %p, offset too large\n", io_u);
-		dprint(FD_IO, "  off=%llu/%lu > %llu\n", io_u->offset,
-				io_u->buflen, io_u->file->real_file_size);
+		dprint(FD_IO, "  off=%llu/%lu > %llu\n",
+			(unsigned long long) io_u->offset, io_u->buflen,
+			(unsigned long long) io_u->file->real_file_size);
 		return 1;
 	}
 
@@ -703,13 +915,9 @@ static int fill_io_u(struct thread_data *td, struct io_u *io_u)
 	if (td_random(td) && file_randommap(td, io_u->file))
 		mark_random_map(td, io_u);
 
-	/*
-	 * If using a write iolog, store this entry.
-	 */
 out:
 	dprint_io_u(io_u, "fill_io_u");
 	td->zone_bytes += io_u->buflen;
-	log_io_u(td, io_u);
 	return 0;
 }
 
@@ -877,6 +1085,34 @@ static void io_u_mark_latency(struct thread_data *td, unsigned long usec)
 		io_u_mark_lat_msec(td, usec / 1000);
 }
 
+static unsigned int __get_next_fileno_rand(struct thread_data *td)
+{
+	unsigned long fileno;
+
+	if (td->o.file_service_type == FIO_FSERVICE_RANDOM) {
+		uint64_t frand_max = rand_max(&td->next_file_state);
+		unsigned long r;
+
+		r = __rand(&td->next_file_state);
+		return (unsigned int) ((double) td->o.nr_files
+				* (r / (frand_max + 1.0)));
+	}
+
+	if (td->o.file_service_type == FIO_FSERVICE_ZIPF)
+		fileno = zipf_next(&td->next_file_zipf);
+	else if (td->o.file_service_type == FIO_FSERVICE_PARETO)
+		fileno = pareto_next(&td->next_file_zipf);
+	else if (td->o.file_service_type == FIO_FSERVICE_GAUSS)
+		fileno = gauss_next(&td->next_file_gauss);
+	else {
+		log_err("fio: bad file service type: %d\n", td->o.file_service_type);
+		assert(0);
+		return 0;
+	}
+
+	return fileno >> FIO_FSERVICE_SHIFT;
+}
+
 /*
  * Get next file to service by choosing one at random
  */
@@ -889,17 +1125,8 @@ static struct fio_file *get_next_file_rand(struct thread_data *td,
 
 	do {
 		int opened = 0;
-		unsigned long r;
 
-		if (td->o.use_os_rand) {
-			r = os_random_long(&td->next_file_state);
-			fno = (unsigned int) ((double) td->o.nr_files
-				* (r / (OS_RAND_MAX + 1.0)));
-		} else {
-			r = __rand(&td->__next_file_state);
-			fno = (unsigned int) ((double) td->o.nr_files
-				* (r / (FRAND_MAX + 1.0)));
-		}
+		fno = __get_next_fileno_rand(td);
 
 		f = td->files[fno];
 		if (fio_file_done(f))
@@ -908,6 +1135,9 @@ static struct fio_file *get_next_file_rand(struct thread_data *td,
 		if (!fio_file_open(f)) {
 			int err;
 
+			if (td->nr_open_files >= td->o.open_files)
+				return ERR_PTR(-EBUSY);
+
 			err = td_io_open_file(td, f);
 			if (err)
 				continue;
@@ -950,6 +1180,9 @@ static struct fio_file *get_next_file_rr(struct thread_data *td, int goodf,
 		if (!fio_file_open(f)) {
 			int err;
 
+			if (td->nr_open_files >= td->o.open_files)
+				return ERR_PTR(-EBUSY);
+
 			err = td_io_open_file(td, f);
 			if (err) {
 				dprint(FD_FILE, "error %d on open of %s\n",
@@ -1003,31 +1236,39 @@ static struct fio_file *__get_next_file(struct thread_data *td)
 	else
 		f = get_next_file_rand(td, FIO_FILE_open, FIO_FILE_closing);
 
+	if (IS_ERR(f))
+		return f;
+
 	td->file_service_file = f;
 	td->file_service_left = td->file_service_nr - 1;
 out:
-	dprint(FD_FILE, "get_next_file: %p [%s]\n", f, f->file_name);
+	if (f)
+		dprint(FD_FILE, "get_next_file: %p [%s]\n", f, f->file_name);
+	else
+		dprint(FD_FILE, "get_next_file: NULL\n");
 	return f;
 }
 
 static struct fio_file *get_next_file(struct thread_data *td)
 {
-	struct prof_io_ops *ops = &td->prof_io_ops;
+	if (td->flags & TD_F_PROFILE_OPS) {
+		struct prof_io_ops *ops = &td->prof_io_ops;
 
-	if (ops->get_next_file)
-		return ops->get_next_file(td);
+		if (ops->get_next_file)
+			return ops->get_next_file(td);
+	}
 
 	return __get_next_file(td);
 }
 
-static int set_io_u_file(struct thread_data *td, struct io_u *io_u)
+static long set_io_u_file(struct thread_data *td, struct io_u *io_u)
 {
 	struct fio_file *f;
 
 	do {
 		f = get_next_file(td);
-		if (!f)
-			return 1;
+		if (IS_ERR_OR_NULL(f))
+			return PTR_ERR(f);
 
 		io_u->file = f;
 		get_file(f);
@@ -1038,50 +1279,215 @@ static int set_io_u_file(struct thread_data *td, struct io_u *io_u)
 		put_file_log(td, f);
 		td_io_close_file(td, f);
 		io_u->file = NULL;
-		fio_file_set_done(f);
-		td->nr_done_files++;
-		dprint(FD_FILE, "%s: is done (%d of %d)\n", f->file_name,
+		if (td->o.file_service_type & __FIO_FSERVICE_NONUNIFORM)
+			fio_file_reset(td, f);
+		else {
+			fio_file_set_done(f);
+			td->nr_done_files++;
+			dprint(FD_FILE, "%s: is done (%d of %d)\n", f->file_name,
 					td->nr_done_files, td->o.nr_files);
+		}
 	} while (1);
 
 	return 0;
 }
 
+static void lat_fatal(struct thread_data *td, struct io_completion_data *icd,
+		      unsigned long tusec, unsigned long max_usec)
+{
+	if (!td->error)
+		log_err("fio: latency of %lu usec exceeds specified max (%lu usec)\n", tusec, max_usec);
+	td_verror(td, ETIMEDOUT, "max latency exceeded");
+	icd->error = ETIMEDOUT;
+}
+
+static void lat_new_cycle(struct thread_data *td)
+{
+	fio_gettime(&td->latency_ts, NULL);
+	td->latency_ios = ddir_rw_sum(td->io_blocks);
+	td->latency_failed = 0;
+}
+
+/*
+ * We had an IO outside the latency target. Reduce the queue depth. If we
+ * are at QD=1, then it's time to give up.
+ */
+static bool __lat_target_failed(struct thread_data *td)
+{
+	if (td->latency_qd == 1)
+		return true;
+
+	td->latency_qd_high = td->latency_qd;
+
+	if (td->latency_qd == td->latency_qd_low)
+		td->latency_qd_low--;
+
+	td->latency_qd = (td->latency_qd + td->latency_qd_low) / 2;
+
+	dprint(FD_RATE, "Ramped down: %d %d %d\n", td->latency_qd_low, td->latency_qd, td->latency_qd_high);
+
+	/*
+	 * When we ramp QD down, quiesce existing IO to prevent
+	 * a storm of ramp downs due to pending higher depth.
+	 */
+	io_u_quiesce(td);
+	lat_new_cycle(td);
+	return false;
+}
+
+static bool lat_target_failed(struct thread_data *td)
+{
+	if (td->o.latency_percentile.u.f == 100.0)
+		return __lat_target_failed(td);
+
+	td->latency_failed++;
+	return false;
+}
+
+void lat_target_init(struct thread_data *td)
+{
+	td->latency_end_run = 0;
+
+	if (td->o.latency_target) {
+		dprint(FD_RATE, "Latency target=%llu\n", td->o.latency_target);
+		fio_gettime(&td->latency_ts, NULL);
+		td->latency_qd = 1;
+		td->latency_qd_high = td->o.iodepth;
+		td->latency_qd_low = 1;
+		td->latency_ios = ddir_rw_sum(td->io_blocks);
+	} else
+		td->latency_qd = td->o.iodepth;
+}
+
+void lat_target_reset(struct thread_data *td)
+{
+	if (!td->latency_end_run)
+		lat_target_init(td);
+}
+
+static void lat_target_success(struct thread_data *td)
+{
+	const unsigned int qd = td->latency_qd;
+	struct thread_options *o = &td->o;
+
+	td->latency_qd_low = td->latency_qd;
+
+	/*
+	 * If we haven't failed yet, we double up to a failing value instead
+	 * of bisecting from highest possible queue depth. If we have set
+	 * a limit other than td->o.iodepth, bisect between that.
+	 */
+	if (td->latency_qd_high != o->iodepth)
+		td->latency_qd = (td->latency_qd + td->latency_qd_high) / 2;
+	else
+		td->latency_qd *= 2;
+
+	if (td->latency_qd > o->iodepth)
+		td->latency_qd = o->iodepth;
+
+	dprint(FD_RATE, "Ramped up: %d %d %d\n", td->latency_qd_low, td->latency_qd, td->latency_qd_high);
+
+	/*
+	 * Same as last one, we are done. Let it run a latency cycle, so
+	 * we get only the results from the targeted depth.
+	 */
+	if (td->latency_qd == qd) {
+		if (td->latency_end_run) {
+			dprint(FD_RATE, "We are done\n");
+			td->done = 1;
+		} else {
+			dprint(FD_RATE, "Quiesce and final run\n");
+			io_u_quiesce(td);
+			td->latency_end_run = 1;
+			reset_all_stats(td);
+			reset_io_stats(td);
+		}
+	}
+
+	lat_new_cycle(td);
+}
+
+/*
+ * Check if we can bump the queue depth
+ */
+void lat_target_check(struct thread_data *td)
+{
+	uint64_t usec_window;
+	uint64_t ios;
+	double success_ios;
+
+	usec_window = utime_since_now(&td->latency_ts);
+	if (usec_window < td->o.latency_window)
+		return;
+
+	ios = ddir_rw_sum(td->io_blocks) - td->latency_ios;
+	success_ios = (double) (ios - td->latency_failed) / (double) ios;
+	success_ios *= 100.0;
+
+	dprint(FD_RATE, "Success rate: %.2f%% (target %.2f%%)\n", success_ios, td->o.latency_percentile.u.f);
+
+	if (success_ios >= td->o.latency_percentile.u.f)
+		lat_target_success(td);
+	else
+		__lat_target_failed(td);
+}
+
+/*
+ * If latency target is enabled, we might be ramping up or down and not
+ * using the full queue depth available.
+ */
+bool queue_full(const struct thread_data *td)
+{
+	const int qempty = io_u_qempty(&td->io_u_freelist);
+
+	if (qempty)
+		return true;
+	if (!td->o.latency_target)
+		return false;
+
+	return td->cur_depth >= td->latency_qd;
+}
 
 struct io_u *__get_io_u(struct thread_data *td)
 {
 	struct io_u *io_u = NULL;
 
+	if (td->stop_io)
+		return NULL;
+
 	td_io_u_lock(td);
 
 again:
-	if (!flist_empty(&td->io_u_requeues))
-		io_u = flist_entry(td->io_u_requeues.next, struct io_u, list);
+	if (!io_u_rempty(&td->io_u_requeues))
+		io_u = io_u_rpop(&td->io_u_requeues);
 	else if (!queue_full(td)) {
-		io_u = flist_entry(td->io_u_freelist.next, struct io_u, list);
+		io_u = io_u_qpop(&td->io_u_freelist);
 
+		io_u->file = NULL;
 		io_u->buflen = 0;
 		io_u->resid = 0;
-		io_u->file = NULL;
 		io_u->end_io = NULL;
 	}
 
 	if (io_u) {
 		assert(io_u->flags & IO_U_F_FREE);
-		io_u->flags &= ~(IO_U_F_FREE | IO_U_F_FREE_DEF);
-		io_u->flags &= ~(IO_U_F_TRIMMED | IO_U_F_BARRIER);
+		io_u_clear(td, io_u, IO_U_F_FREE | IO_U_F_NO_FILE_PUT |
+				 IO_U_F_TRIMMED | IO_U_F_BARRIER |
+				 IO_U_F_VER_LIST);
 
 		io_u->error = 0;
-		flist_del(&io_u->list);
-		flist_add(&io_u->list, &td->io_u_busylist);
+		io_u->acct_ddir = -1;
 		td->cur_depth++;
-		io_u->flags |= IO_U_F_IN_CUR_DEPTH;
-	} else if (td->o.verify_async) {
+		assert(!(td->flags & TD_F_CHILD));
+		io_u_set(td, io_u, IO_U_F_IN_CUR_DEPTH);
+		io_u->ipo = NULL;
+	} else if (td_async_processing(td)) {
 		/*
 		 * We ran out, wait for async verify threads to finish and
 		 * return one
 		 */
-		pthread_cond_wait(&td->free_cond, &td->io_u_lock);
+		assert(!(td->flags & TD_F_CHILD));
+		assert(!pthread_cond_wait(&td->free_cond, &td->io_u_lock));
 		goto again;
 	}
 
@@ -1089,9 +1495,12 @@ again:
 	return io_u;
 }
 
-static int check_get_trim(struct thread_data *td, struct io_u *io_u)
+static bool check_get_trim(struct thread_data *td, struct io_u *io_u)
 {
-	if (td->o.trim_backlog && td->trim_entries) {
+	if (!(td->flags & TD_F_TRIM_BACKLOG))
+		return false;
+
+	if (td->trim_entries) {
 		int get_trim = 0;
 
 		if (td->trim_batch) {
@@ -1105,22 +1514,24 @@ static int check_get_trim(struct thread_data *td, struct io_u *io_u)
 			get_trim = 1;
 		}
 
-		if (get_trim && !get_next_trim(td, io_u))
-			return 1;
+		if (get_trim && get_next_trim(td, io_u))
+			return true;
 	}
 
-	return 0;
+	return false;
 }
 
-static int check_get_verify(struct thread_data *td, struct io_u *io_u)
+static bool check_get_verify(struct thread_data *td, struct io_u *io_u)
 {
-	if (td->o.verify_backlog && td->io_hist_len) {
+	if (!(td->flags & TD_F_VER_BACKLOG))
+		return false;
+
+	if (td->io_hist_len) {
 		int get_verify = 0;
 
-		if (td->verify_batch) {
-			td->verify_batch--;
+		if (td->verify_batch)
 			get_verify = 1;
-		} else if (!(td->io_hist_len % td->o.verify_backlog) &&
+		else if (!(td->io_hist_len % td->o.verify_backlog) &&
 			 td->last_ddir != DDIR_READ) {
 			td->verify_batch = td->o.verify_batch;
 			if (!td->verify_batch)
@@ -1128,11 +1539,13 @@ static int check_get_verify(struct thread_data *td, struct io_u *io_u)
 			get_verify = 1;
 		}
 
-		if (get_verify && !get_next_verify(td, io_u))
-			return 1;
+		if (get_verify && !get_next_verify(td, io_u)) {
+			td->verify_batch--;
+			return true;
+		}
 	}
 
-	return 0;
+	return false;
 }
 
 /*
@@ -1144,7 +1557,7 @@ static int check_get_verify(struct thread_data *td, struct io_u *io_u)
 static void small_content_scramble(struct io_u *io_u)
 {
 	unsigned int i, nr_blocks = io_u->buflen / 512;
-	unsigned long long boffset;
+	uint64_t boffset;
 	unsigned int offset;
 	void *p, *end;
 
@@ -1162,9 +1575,9 @@ static void small_content_scramble(struct io_u *io_u)
 		 * and the actual offset.
 		 */
 		offset = (io_u->start_time.tv_usec ^ boffset) & 511;
-		offset &= ~(sizeof(unsigned long long) - 1);
-		if (offset >= 512 - sizeof(unsigned long long))
-			offset -= sizeof(unsigned long long);
+		offset &= ~(sizeof(uint64_t) - 1);
+		if (offset >= 512 - sizeof(uint64_t))
+			offset -= sizeof(uint64_t);
 		memcpy(p + offset, &boffset, sizeof(boffset));
 
 		end = p + 512 - sizeof(io_u->start_time);
@@ -1183,6 +1596,7 @@ struct io_u *get_io_u(struct thread_data *td)
 	struct fio_file *f;
 	struct io_u *io_u;
 	int do_scramble = 0;
+	long ret = 0;
 
 	io_u = __get_io_u(td);
 	if (!io_u) {
@@ -1204,33 +1618,44 @@ struct io_u *get_io_u(struct thread_data *td)
 	/*
 	 * If using an iolog, grab next piece if any available.
 	 */
-	if (td->o.read_iolog_file) {
+	if (td->flags & TD_F_READ_IOLOG) {
 		if (read_iolog_get(td, io_u))
 			goto err_put;
 	} else if (set_io_u_file(td, io_u)) {
+		ret = -EBUSY;
 		dprint(FD_IO, "io_u %p, setting file failed\n", io_u);
 		goto err_put;
 	}
 
 	f = io_u->file;
+	if (!f) {
+		dprint(FD_IO, "io_u %p, setting file failed\n", io_u);
+		goto err_put;
+	}
+
 	assert(fio_file_open(f));
 
 	if (ddir_rw(io_u->ddir)) {
-		if (!io_u->buflen && !(td->io_ops->flags & FIO_NOIO)) {
+		if (!io_u->buflen && !td_ioengine_flagged(td, FIO_NOIO)) {
 			dprint(FD_IO, "get_io_u: zero buflen on %p\n", io_u);
 			goto err_put;
 		}
 
-		f->last_start = io_u->offset;
-		f->last_pos = io_u->offset + io_u->buflen;
+		f->last_start[io_u->ddir] = io_u->offset;
+		f->last_pos[io_u->ddir] = io_u->offset + io_u->buflen;
 
 		if (io_u->ddir == DDIR_WRITE) {
-			if (td->o.verify != VERIFY_NONE)
-				populate_verify_io_u(td, io_u);
-			else if (td->o.refill_buffers)
-				io_u_fill_buffer(td, io_u, io_u->xfer_buflen);
-			else if (td->o.scramble_buffers)
+			if (td->flags & TD_F_REFILL_BUFFERS) {
+				io_u_fill_buffer(td, io_u,
+					td->o.min_bs[DDIR_WRITE],
+					io_u->buflen);
+			} else if ((td->flags & TD_F_SCRAMBLE_BUFFERS) &&
+				   !(td->flags & TD_F_COMPRESS))
 				do_scramble = 1;
+			if (td->flags & TD_F_VER_NONE) {
+				populate_verify_io_u(td, io_u);
+				do_scramble = 0;
+			}
 		} else if (io_u->ddir == DDIR_READ) {
 			/*
 			 * Reset the buf_filled parameters so next time if the
@@ -1249,7 +1674,7 @@ struct io_u *get_io_u(struct thread_data *td)
 out:
 	assert(io_u->file);
 	if (!td_io_prep(td, io_u)) {
-		if (!td->o.disable_slat)
+		if (!td->o.disable_lat)
 			fio_gettime(&io_u->start_time, NULL);
 		if (do_scramble)
 			small_content_scramble(io_u);
@@ -1258,90 +1683,159 @@ out:
 err_put:
 	dprint(FD_IO, "get_io_u failed\n");
 	put_io_u(td, io_u);
-	return NULL;
+	return ERR_PTR(ret);
 }
 
-void io_u_log_error(struct thread_data *td, struct io_u *io_u)
+static void __io_u_log_error(struct thread_data *td, struct io_u *io_u)
 {
-	const char *msg[] = { "read", "write", "sync", "datasync",
-				"sync_file_range", "wait", "trim" };
+	enum error_type_bit eb = td_error_type(io_u->ddir, io_u->error);
 
+	if (td_non_fatal_error(td, eb, io_u->error) && !td->o.error_dump)
+		return;
 
+	log_err("fio: io_u error%s%s: %s: %s offset=%llu, buflen=%lu\n",
+		io_u->file ? " on file " : "",
+		io_u->file ? io_u->file->file_name : "",
+		strerror(io_u->error),
+		io_ddir_name(io_u->ddir),
+		io_u->offset, io_u->xfer_buflen);
 
-	log_err("fio: io_u error");
-
-	if (io_u->file)
-		log_err(" on file %s", io_u->file->file_name);
-
-	log_err(": %s\n", strerror(io_u->error));
+	if (td->io_ops->errdetails) {
+		char *err = td->io_ops->errdetails(io_u);
 
-	log_err("     %s offset=%llu, buflen=%lu\n", msg[io_u->ddir],
-					io_u->offset, io_u->xfer_buflen);
+		log_err("fio: %s\n", err);
+		free(err);
+	}
 
 	if (!td->error)
 		td_verror(td, io_u->error, "io_u error");
 }
 
+void io_u_log_error(struct thread_data *td, struct io_u *io_u)
+{
+	__io_u_log_error(td, io_u);
+	if (td->parent)
+		__io_u_log_error(td->parent, io_u);
+}
+
+static inline bool gtod_reduce(struct thread_data *td)
+{
+	return (td->o.disable_clat && td->o.disable_slat && td->o.disable_bw)
+			|| td->o.gtod_reduce;
+}
+
 static void account_io_completion(struct thread_data *td, struct io_u *io_u,
 				  struct io_completion_data *icd,
 				  const enum fio_ddir idx, unsigned int bytes)
 {
-	unsigned long uninitialized_var(lusec);
+	const int no_reduce = !gtod_reduce(td);
+	unsigned long lusec = 0;
 
-	if (!icd->account)
-		return;
+	if (td->parent)
+		td = td->parent;
 
-	if (!td->o.disable_clat || !td->o.disable_bw)
+	if (no_reduce)
 		lusec = utime_since(&io_u->issue_time, &icd->time);
 
 	if (!td->o.disable_lat) {
 		unsigned long tusec;
 
 		tusec = utime_since(&io_u->start_time, &icd->time);
-		add_lat_sample(td, idx, tusec, bytes);
-	}
+		add_lat_sample(td, idx, tusec, bytes, io_u->offset);
+
+		if (td->flags & TD_F_PROFILE_OPS) {
+			struct prof_io_ops *ops = &td->prof_io_ops;
+
+			if (ops->io_u_lat)
+				icd->error = ops->io_u_lat(td, tusec);
+		}
 
-	if (!td->o.disable_clat) {
-		add_clat_sample(td, idx, lusec, bytes);
-		io_u_mark_latency(td, lusec);
+		if (td->o.max_latency && tusec > td->o.max_latency)
+			lat_fatal(td, icd, tusec, td->o.max_latency);
+		if (td->o.latency_target && tusec > td->o.latency_target) {
+			if (lat_target_failed(td))
+				lat_fatal(td, icd, tusec, td->o.latency_target);
+		}
 	}
 
-	if (!td->o.disable_bw)
-		add_bw_sample(td, idx, bytes, &icd->time);
+	if (ddir_rw(idx)) {
+		if (!td->o.disable_clat) {
+			add_clat_sample(td, idx, lusec, bytes, io_u->offset);
+			io_u_mark_latency(td, lusec);
+		}
+
+		if (!td->o.disable_bw && per_unit_log(td->bw_log))
+			add_bw_sample(td, io_u, bytes, lusec);
 
-	add_iops_sample(td, idx, &icd->time);
+		if (no_reduce && per_unit_log(td->iops_log))
+			add_iops_sample(td, io_u, bytes);
+	}
+
+	if (td->ts.nr_block_infos && io_u->ddir == DDIR_TRIM) {
+		uint32_t *info = io_u_block_info(td, io_u);
+		if (BLOCK_INFO_STATE(*info) < BLOCK_STATE_TRIM_FAILURE) {
+			if (io_u->ddir == DDIR_TRIM) {
+				*info = BLOCK_INFO(BLOCK_STATE_TRIMMED,
+						BLOCK_INFO_TRIMS(*info) + 1);
+			} else if (io_u->ddir == DDIR_WRITE) {
+				*info = BLOCK_INFO_SET_STATE(BLOCK_STATE_WRITTEN,
+								*info);
+			}
+		}
+	}
 }
 
-static long long usec_for_io(struct thread_data *td, enum fio_ddir ddir)
+static void file_log_write_comp(const struct thread_data *td, struct fio_file *f,
+				uint64_t offset, unsigned int bytes)
 {
-	unsigned long long secs, remainder, bps, bytes;
-	bytes = td->this_io_bytes[ddir];
-	bps = td->rate_bps[ddir];
-	secs = bytes / bps;
-	remainder = bytes % bps;
-	return remainder * 1000000 / bps + secs * 1000000;
+	int idx;
+
+	if (!f)
+		return;
+
+	if (f->first_write == -1ULL || offset < f->first_write)
+		f->first_write = offset;
+	if (f->last_write == -1ULL || ((offset + bytes) > f->last_write))
+		f->last_write = offset + bytes;
+
+	if (!f->last_write_comp)
+		return;
+
+	idx = f->last_write_idx++;
+	f->last_write_comp[idx] = offset;
+	if (f->last_write_idx == td->o.iodepth)
+		f->last_write_idx = 0;
 }
 
-static void io_completed(struct thread_data *td, struct io_u *io_u,
+static void io_completed(struct thread_data *td, struct io_u **io_u_ptr,
 			 struct io_completion_data *icd)
 {
-	/*
-	 * Older gcc's are too dumb to realize that usec is always used
-	 * initialized, silence that warning.
-	 */
-	unsigned long uninitialized_var(usec);
-	struct fio_file *f;
+	struct io_u *io_u = *io_u_ptr;
+	enum fio_ddir ddir = io_u->ddir;
+	struct fio_file *f = io_u->file;
 
 	dprint_io_u(io_u, "io complete");
 
-	td_io_u_lock(td);
 	assert(io_u->flags & IO_U_F_FLIGHT);
-	io_u->flags &= ~(IO_U_F_FLIGHT | IO_U_F_BUSY_OK);
-	td_io_u_unlock(td);
+	io_u_clear(td, io_u, IO_U_F_FLIGHT | IO_U_F_BUSY_OK);
+
+	/*
+	 * Mark IO ok to verify
+	 */
+	if (io_u->ipo) {
+		/*
+		 * Remove errored entry from the verification list
+		 */
+		if (io_u->error)
+			unlog_io_piece(td, io_u);
+		else {
+			io_u->ipo->flags &= ~IP_F_IN_FLIGHT;
+			write_barrier();
+		}
+	}
 
-	if (ddir_sync(io_u->ddir)) {
+	if (ddir_sync(ddir)) {
 		td->last_was_sync = 1;
-		f = io_u->file;
 		if (f) {
 			f->first_write = -1ULL;
 			f->last_write = -1ULL;
@@ -1350,55 +1844,31 @@ static void io_completed(struct thread_data *td, struct io_u *io_u,
 	}
 
 	td->last_was_sync = 0;
-	td->last_ddir = io_u->ddir;
+	td->last_ddir = ddir;
 
-	if (!io_u->error && ddir_rw(io_u->ddir)) {
+	if (!io_u->error && ddir_rw(ddir)) {
 		unsigned int bytes = io_u->buflen - io_u->resid;
-		const enum fio_ddir idx = io_u->ddir;
-		const enum fio_ddir odx = io_u->ddir ^ 1;
 		int ret;
 
-		td->io_blocks[idx]++;
-		td->this_io_blocks[idx]++;
-		td->io_bytes[idx] += bytes;
-		td->this_io_bytes[idx] += bytes;
-
-		if (idx == DDIR_WRITE) {
-			f = io_u->file;
-			if (f) {
-				if (f->first_write == -1ULL ||
-				    io_u->offset < f->first_write)
-					f->first_write = io_u->offset;
-				if (f->last_write == -1ULL ||
-				    ((io_u->offset + bytes) > f->last_write))
-					f->last_write = io_u->offset + bytes;
-			}
-		}
+		td->io_blocks[ddir]++;
+		td->this_io_blocks[ddir]++;
+		td->io_bytes[ddir] += bytes;
 
-		if (ramp_time_over(td) && (td->runstate == TD_RUNNING ||
-					   td->runstate == TD_VERIFYING)) {
-			account_io_completion(td, io_u, icd, idx, bytes);
+		if (!(io_u->flags & IO_U_F_VER_LIST))
+			td->this_io_bytes[ddir] += bytes;
 
-			if (__should_check_rate(td, idx)) {
-				td->rate_pending_usleep[idx] =
-					(usec_for_io(td, idx) -
-					 utime_since_now(&td->start));
-			}
-			if (__should_check_rate(td, odx))
-				td->rate_pending_usleep[odx] =
-					(usec_for_io(td, odx) -
-					 utime_since_now(&td->start));
-		}
+		if (ddir == DDIR_WRITE)
+			file_log_write_comp(td, f, io_u->offset, bytes);
 
-		if (td_write(td) && idx == DDIR_WRITE &&
-		    td->o.do_verify &&
-		    td->o.verify != VERIFY_NONE)
-			log_io_piece(td, io_u);
+		if (ramp_time_over(td) && (td->runstate == TD_RUNNING ||
+					   td->runstate == TD_VERIFYING))
+			account_io_completion(td, io_u, icd, ddir, bytes);
 
-		icd->bytes_done[idx] += bytes;
+		icd->bytes_done[ddir] += bytes;
 
 		if (io_u->end_io) {
-			ret = io_u->end_io(td, io_u);
+			ret = io_u->end_io(td, io_u_ptr);
+			io_u = *io_u_ptr;
 			if (ret && !icd->error)
 				icd->error = ret;
 		}
@@ -1406,8 +1876,12 @@ static void io_completed(struct thread_data *td, struct io_u *io_u,
 		icd->error = io_u->error;
 		io_u_log_error(td, io_u);
 	}
-	if (icd->error && td_non_fatal_error(icd->error) &&
-           (td->o.continue_on_error & td_error_type(io_u->ddir, icd->error))) {
+	if (icd->error) {
+		enum error_type_bit eb = td_error_type(ddir, icd->error);
+
+		if (!td_non_fatal_error(td, eb, icd->error))
+			return;
+
 		/*
 		 * If there is a non_fatal error, then add to the error count
 		 * and clear all the errors.
@@ -1415,21 +1889,24 @@ static void io_completed(struct thread_data *td, struct io_u *io_u,
 		update_error_count(td, icd->error);
 		td_clear_error(td);
 		icd->error = 0;
-		io_u->error = 0;
+		if (io_u)
+			io_u->error = 0;
 	}
 }
 
 static void init_icd(struct thread_data *td, struct io_completion_data *icd,
 		     int nr)
 {
-	if (!td->o.disable_clat || !td->o.disable_bw)
+	int ddir;
+
+	if (!gtod_reduce(td))
 		fio_gettime(&icd->time, NULL);
 
 	icd->nr = nr;
-	icd->account = 1;
 
 	icd->error = 0;
-	icd->bytes_done[0] = icd->bytes_done[1] = 0;
+	for (ddir = 0; ddir < DDIR_RWDIR_CNT; ddir++)
+		icd->bytes_done[ddir] = 0;
 }
 
 static void ios_completed(struct thread_data *td,
@@ -1441,27 +1918,25 @@ static void ios_completed(struct thread_data *td,
 	for (i = 0; i < icd->nr; i++) {
 		io_u = td->io_ops->event(td, i);
 
-		io_completed(td, io_u, icd);
+		io_completed(td, &io_u, icd);
 
-		if (!(io_u->flags & IO_U_F_FREE_DEF))
+		if (io_u)
 			put_io_u(td, io_u);
-
-		icd->account = 0;
 	}
 }
 
 /*
  * Complete a single io_u for the sync engines.
  */
-int io_u_sync_complete(struct thread_data *td, struct io_u *io_u,
-		       unsigned long *bytes)
+int io_u_sync_complete(struct thread_data *td, struct io_u *io_u)
 {
 	struct io_completion_data icd;
+	int ddir;
 
 	init_icd(td, &icd, 1);
-	io_completed(td, io_u, &icd);
+	io_completed(td, &io_u, &icd);
 
-	if (!(io_u->flags & IO_U_F_FREE_DEF))
+	if (io_u)
 		put_io_u(td, io_u);
 
 	if (icd.error) {
@@ -1469,10 +1944,8 @@ int io_u_sync_complete(struct thread_data *td, struct io_u *io_u,
 		return -1;
 	}
 
-	if (bytes) {
-		bytes[0] += icd.bytes_done[0];
-		bytes[1] += icd.bytes_done[1];
-	}
+	for (ddir = 0; ddir < DDIR_RWDIR_CNT; ddir++)
+		td->bytes_done[ddir] += icd.bytes_done[ddir];
 
 	return 0;
 }
@@ -1480,20 +1953,23 @@ int io_u_sync_complete(struct thread_data *td, struct io_u *io_u,
 /*
  * Called to complete min_events number of io for the async engines.
  */
-int io_u_queued_complete(struct thread_data *td, int min_evts,
-			 unsigned long *bytes)
+int io_u_queued_complete(struct thread_data *td, int min_evts)
 {
 	struct io_completion_data icd;
 	struct timespec *tvp = NULL;
-	int ret;
+	int ret, ddir;
 	struct timespec ts = { .tv_sec = 0, .tv_nsec = 0, };
 
 	dprint(FD_IO, "io_u_queued_completed: min=%d\n", min_evts);
 
 	if (!min_evts)
 		tvp = &ts;
+	else if (min_evts > td->cur_depth)
+		min_evts = td->cur_depth;
 
-	ret = td_io_getevents(td, min_evts, td->o.iodepth_batch_complete, tvp);
+	/* No worries, td_io_getevents fixes min and max if they are
+	 * set incorrectly */
+	ret = td_io_getevents(td, min_evts, td->o.iodepth_batch_complete_max, tvp);
 	if (ret < 0) {
 		td_verror(td, -ret, "td_io_getevents");
 		return ret;
@@ -1507,12 +1983,10 @@ int io_u_queued_complete(struct thread_data *td, int min_evts,
 		return -1;
 	}
 
-	if (bytes) {
-		bytes[0] += icd.bytes_done[0];
-		bytes[1] += icd.bytes_done[1];
-	}
+	for (ddir = 0; ddir < DDIR_RWDIR_CNT; ddir++)
+		td->bytes_done[ddir] += icd.bytes_done[ddir];
 
-	return 0;
+	return ret;
 }
 
 /*
@@ -1524,20 +1998,92 @@ void io_u_queued(struct thread_data *td, struct io_u *io_u)
 		unsigned long slat_time;
 
 		slat_time = utime_since(&io_u->start_time, &io_u->issue_time);
-		add_slat_sample(td, io_u->ddir, slat_time, io_u->xfer_buflen);
+
+		if (td->parent)
+			td = td->parent;
+
+		add_slat_sample(td, io_u->ddir, slat_time, io_u->xfer_buflen,
+				io_u->offset);
+	}
+}
+
+/*
+ * See if we should reuse the last seed, if dedupe is enabled
+ */
+static struct frand_state *get_buf_state(struct thread_data *td)
+{
+	unsigned int v;
+
+	if (!td->o.dedupe_percentage)
+		return &td->buf_state;
+	else if (td->o.dedupe_percentage == 100) {
+		frand_copy(&td->buf_state_prev, &td->buf_state);
+		return &td->buf_state;
 	}
+
+	v = rand32_between(&td->dedupe_state, 1, 100);
+
+	if (v <= td->o.dedupe_percentage)
+		return &td->buf_state_prev;
+
+	return &td->buf_state;
+}
+
+static void save_buf_state(struct thread_data *td, struct frand_state *rs)
+{
+	if (td->o.dedupe_percentage == 100)
+		frand_copy(rs, &td->buf_state_prev);
+	else if (rs == &td->buf_state)
+		frand_copy(&td->buf_state_prev, rs);
+}
+
+void fill_io_buffer(struct thread_data *td, void *buf, unsigned int min_write,
+		    unsigned int max_bs)
+{
+	struct thread_options *o = &td->o;
+
+	if (o->compress_percentage || o->dedupe_percentage) {
+		unsigned int perc = td->o.compress_percentage;
+		struct frand_state *rs;
+		unsigned int left = max_bs;
+		unsigned int this_write;
+
+		do {
+			rs = get_buf_state(td);
+
+			min_write = min(min_write, left);
+
+			if (perc) {
+				this_write = min_not_zero(min_write,
+							td->o.compress_chunk);
+
+				fill_random_buf_percentage(rs, buf, perc,
+					this_write, this_write,
+					o->buffer_pattern,
+					o->buffer_pattern_bytes);
+			} else {
+				fill_random_buf(rs, buf, min_write);
+				this_write = min_write;
+			}
+
+			buf += this_write;
+			left -= this_write;
+			save_buf_state(td, rs);
+		} while (left);
+	} else if (o->buffer_pattern_bytes)
+		fill_buffer_pattern(td, buf, max_bs);
+	else if (o->zero_buffers)
+		memset(buf, 0, max_bs);
+	else
+		fill_random_buf(get_buf_state(td), buf, max_bs);
 }
 
 /*
  * "randomly" fill the buffer contents
  */
 void io_u_fill_buffer(struct thread_data *td, struct io_u *io_u,
-		      unsigned int max_bs)
+		      unsigned int min_write, unsigned int max_bs)
 {
 	io_u->buf_filled_len = 0;
-
-	if (!td->o.zero_buffers)
-		fill_random_buf(&td->buf_state, io_u->buf, max_bs);
-	else
-		memset(io_u->buf, 0, max_bs);
+	fill_io_buffer(td, io_u->buf, min_write, max_bs);
 }