Update documentation for mmapshared (MMAP_SHARED)

[fio.git] / fio.1

diff --git a/fio.1 b/fio.1
index aea9f348512b2529fdd848459b76afd3e1908739..3bd3318219eef54b9ee55ca2d0179378c2f681a9 100644 (file)
--- a/fio.1
+++ b/fio.1
@@ -22,6 +22,7 @@ Write output to \fIfilename\fR.
 .TP
 .BI \-\-output-format \fR=\fPformat
 Set the reporting format to \fInormal\fR, \fIterse\fR, or \fIjson\fR.
+Multiple formats can be selected, separate by a comma.
 .TP
 .BI \-\-runtime \fR=\fPruntime
 Limit run time to \fIruntime\fR seconds.
@@ -34,6 +35,7 @@ Print statistics in a terse, semicolon-delimited format.
 .TP
 .B \-\-append-terse
 Print statistics in selected mode AND terse, semicolon-delimited format.
+Deprecated, use \-\-output-format instead to select multiple formats.
 .TP
 .B \-\-version
 Display version information and exit.
@@ -704,7 +706,7 @@ which means that we submit each IO as soon as it is available, but can
 be raised to submit bigger batches of IO at the time. If it is set to 0
 the \fBiodepth\fR value will be used.
 .TP
-.BI iodepth_batch_complete \fR=\fPint
+.BI iodepth_batch_complete_min \fR=\fPint "\fR,\fP iodepth_batch_complete" \fR=\fPint
 This defines how many pieces of IO to retrieve at once. It defaults to 1 which
  means that we'll ask for a minimum of 1 IO in the retrieval process from the
 kernel. The IO retrieval will go on until we hit the limit set by
@@ -712,6 +714,38 @@ kernel. The IO retrieval will go on until we hit the limit set by
 completed events before queuing more IO. This helps reduce IO latency, at the
 cost of more retrieval system calls.
 .TP
+.BI iodepth_batch_complete_max \fR=\fPint
+This defines maximum pieces of IO to
+retrieve at once. This variable should be used along with
+\fBiodepth_batch_complete_min\fR=int variable, specifying the range
+of min and max amount of IO which should be retrieved. By default
+it is equal to \fBiodepth_batch_complete_min\fR value.
+
+Example #1:
+.RS
+.RS
+\fBiodepth_batch_complete_min\fR=1
+.LP
+\fBiodepth_batch_complete_max\fR=<iodepth>
+.RE
+
+which means that we will retrieve at leat 1 IO and up to the
+whole submitted queue depth. If none of IO has been completed
+yet, we will wait.
+
+Example #2:
+.RS
+\fBiodepth_batch_complete_min\fR=0
+.LP
+\fBiodepth_batch_complete_max\fR=<iodepth>
+.RE
+
+which means that we can retrieve up to the whole submitted
+queue depth, but if none of IO has been completed yet, we will
+NOT wait and immediately exit the system call. In this example
+we simply do polling.
+.RE
+.TP
 .BI iodepth_low \fR=\fPint
 Low watermark indicating when to start filling the queue again.  Default:
 \fBiodepth\fR. 
@@ -1050,6 +1084,9 @@ is given after the option in the format `:\fIfile\fR'.
 .TP
 .B mmaphuge
 Same as \fBmmap\fR, but use huge files as backing.
+.TP
+.B mmapshared
+Same as \fBmmap\fR, but use a MMAP_SHARED mapping.
 .RE
 .P
 The amount of memory allocated is the maximum allowed \fBblocksize\fR for the