Fio has an internal allocator for shared memory called smalloc. It
allocates shared structures from this pool. The pool defaults to 1024k
-in size, and can grow to 32 pools. If running large jobs with randommap
+in size, and can grow to 128 pools. If running large jobs with randommap
enabled it can run out of memory, in which case the --alloc-size switch
-is handy for starting with a larger pool size.
+is handy for starting with a larger pool size. The backing store is
+files in /tmp. Fio cleans up after itself, while it is running you
+may see .fio_smalloc.* files in /tmp.
Job file
also include k/m postfix.
direct=x 1 for direct IO, 0 for buffered IO
thinktime=x "Think" x usec after each io
- rate=x Throttle rate to x KiB/sec
- ratemin=x Quit if rate of x KiB/sec can't be met
+ rate=x Throttle rate to x KB/sec
+ ratemin=x Quit if rate of x KB/sec can't be met
ratecycle=x ratemin averaged over x msecs
cpumask=x Only allow job to run on CPUs defined by mask.
cpus_allowed=x Like 'cpumask', but allow text setting of CPU affinity.
cpuchunks=x Split burn cycles into pieces of x usecs.
+
+Platforms
+---------
+
+Fio works on (at least) Linux, Solaris, and FreeBSD. Some features and/or
+options may only be available on some of the platforms, typically because
+those features only apply to that platform (like the solarisaio engine, or
+the splice engine on Linux).
+
+Some features are not available on FreeBSD/Solaris even if they could be
+implemented, I'd be happy to take patches for that. An example of that is
+disk utility statistics and (I think) huge page support, support for that
+does exist in FreeBSD/Solaris.
+
+Fio uses pthread mutexes for signalling and locking and FreeBSD does not
+support process shared pthread mutexes. As a result, only threads are
+supported on FreeBSD. This could be fixed with sysv ipc locking or
+other locking alternatives.
+
+Other *BSD platforms are untested, but fio should work there almost out
+of the box. Since I don't do test runs or even compiles on those platforms,
+your mileage may vary. Sending me patches for other platforms is greatly
+appreciated. There's a lot of value in having the same test/benchmark tool
+available on all platforms.
+
+
+
Author
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