Add option to manually seed the random generators

[fio.git] / fio.1

diff --git a/fio.1 b/fio.1
index e910e0102e76ff756c3cd85217df3d6123ba3a54..6c3dd21bab61bea09d839ae984c00a540b2255eb 100644 (file)
--- a/fio.1
+++ b/fio.1
@@ -288,6 +288,11 @@ set, the fio will sum the results and report them as "mixed" instead.
 Seed the random number generator in a predictable way so results are repeatable
 across runs.  Default: true.
 .TP
+.BI randseed \fR=\fPint
+Seed the random number generators based on this seed value, to be able to
+control what sequence of output is being generated. If not set, the random
+sequence depends on the \fBrandrepeat\fR setting.
+.TP
 .BI use_os_rand \fR=\fPbool
 Fio can either use the random generator supplied by the OS to generator random
 offsets, or it can use it's own internal generator (based on Tausworthe).
@@ -569,6 +574,11 @@ Low watermark indicating when to start filling the queue again.  Default:
 .BI direct \fR=\fPbool
 If true, use non-buffered I/O (usually O_DIRECT).  Default: false.
 .TP
+.BI atomic \fR=\fPbool
+If value is true, attempt to use atomic direct IO. Atomic writes are guaranteed
+to be stable once acknowledged by the operating system. Only Linux supports
+O_ATOMIC right now.
+.TP
 .BI buffered \fR=\fPbool
 If true, use buffered I/O.  This is the opposite of the \fBdirect\fR parameter.
 Default: true.
@@ -759,6 +769,23 @@ is used for read vs write separation.
 Average bandwidth for \fBrate\fR and \fBratemin\fR over this number of
 milliseconds.  Default: 1000ms.
 .TP
+.BI latency_target \fR=\fPint
+If set, fio will attempt to find the max performance point that the given
+workload will run at while maintaining a latency below this target. The
+values is given in microseconds. See \fBlatency_window\fR and
+\fBlatency_percentile\fR.
+.TP
+.BI latency_window \fR=\fPint
+Used with \fBlatency_target\fR to specify the sample window that the job
+is run at varying queue depths to test the performance. The value is given
+in microseconds.
+.TP
+.BI latency_percentile \fR=\fPfloat
+The percentage of IOs that must fall within the criteria specified by
+\fBlatency_target\fR and \fBlatency_window\fR. If not set, this defaults
+to 100.0, meaning that all IOs must be equal or below to the value set
+by \fBlatency_target\fR.
+.TP
 .BI max_latency \fR=\fPint
 If set, fio will exit the job if it exceeds this maximum latency. It will exit
 with an ETIME error.