Update cpus_allowed_policy=split documentation

[fio.git] / HOWTO

diff --git a/HOWTO b/HOWTO
index c3672d85d361638e532434a758b05f31a429a424..9a9f02a7bf6ec688a8bb5b546d6879a255de3990 100644 (file)
--- a/HOWTO
+++ b/HOWTO
@@ -223,7 +223,8 @@ a string. The following types are used:
 str    String. This is a sequence of alpha characters.
 time   Integer with possible time suffix. In seconds unless otherwise
        specified, use eg 10m for 10 minutes. Accepts s/m/h for seconds,
-       minutes, and hours.
+       minutes, and hours, and accepts 'ms' (or 'msec') for milliseconds,
+       and 'us' (or 'usec') for microseconds.
 int    SI integer. A whole number value, which may contain a suffix
        describing the base of the number. Accepted suffixes are k/m/g/t/p,
        meaning kilo, mega, giga, tera, and peta. The suffix is not case
@@ -927,6 +928,18 @@ cpus_allowed=str Controls the same options as cpumask, but it allows a text
                allows a range of CPUs. Say you wanted a binding to CPUs
                1, 5, and 8-15, you would set cpus_allowed=1,5,8-15.
 
+cpus_allowed_policy=str Set the policy of how fio distributes the CPUs
+               specified by cpus_allowed or cpumask. Two policies are
+               supported:
+
+               shared  All jobs will share the CPU set specified.
+               split   Each job will get a unique CPU from the CPU set.
+
+               'shared' is the default behaviour, if the option isn't
+               specified. If split is specified, then fio will will assign
+               one cpu per job. If not enough CPUs are given for the jobs
+               listed, then fio will roundrobin the CPUs in the set.
+
 numa_cpu_nodes=str Set this job running on spcified NUMA nodes' CPUs. The
                arguments allow comma delimited list of cpu numbers,
                A-B ranges, or 'all'. Note, to enable numa options support,
@@ -1068,6 +1081,13 @@ loops=int        Run the specified number of iterations of this job. Used
                to repeat the same workload a given number of times. Defaults
                to 1.
 
+verify_only    Do not perform specified workload---only verify data still
+               matches previous invocation of this workload. This option
+               allows one to check data multiple times at a later date
+               without overwriting it. This option makes sense only for
+               workloads that write data, and does not support workloads
+               with the time_based option set.
+
 do_verify=bool Run the verify phase after a write phase. Only makes sense if
                verify is set. Defaults to 1.
 
@@ -1098,6 +1118,10 @@ verify=str       If writing to a file, fio can verify the file contents
                        crc7    Use a crc7 sum of the data area and store
                                it in the header of each block.
 
+                       xxhash  Use xxhash as the checksum function. Generally
+                               the fastest software checksum that fio
+                               supports.
+
                        sha512  Use sha512 as the checksum function.
 
                        sha256  Use sha256 as the checksum function.
@@ -1106,7 +1130,9 @@ verify=str        If writing to a file, fio can verify the file contents
 
                        meta    Write extra information about each io
                                (timestamp, block number etc.). The block
-                               number is verified. See also verify_pattern.
+                               number is verified. The io sequence number is
+                               verified for workloads that write data.
+                               See also verify_pattern.
 
                        null    Only pretend to verify. Useful for testing
                                internals with ioengine=null, not for much
@@ -1496,7 +1522,9 @@ that defines them is selected.
 [net] proto=str        The network protocol to use. Accepted values are:
 
                        tcp     Transmission control protocol
+                       tcpv6   Transmission control protocol V6
                        udp     User datagram protocol
+                       udpv6   User datagram protocol V6
                        unix    UNIX domain socket
 
                When the protocol is TCP or UDP, the port must also be given,