Add support for async IO verification offload

[fio.git] / fio.1

diff --git a/fio.1 b/fio.1
index 637304e5ffe7c8368a2b611cb8897566a31e4830..7b1fc8029008e683b17cb4710ea586285e1c0cd8 100644 (file)
--- a/fio.1
+++ b/fio.1
@@ -365,6 +365,10 @@ Offset in the file to start I/O. Data before the offset will not be touched.
 How many I/Os to perform before issuing an \fBfsync\fR\|(2) of dirty data.  If
 0, don't sync.  Default: 0.
 .TP
 How many I/Os to perform before issuing an \fBfsync\fR\|(2) of dirty data.  If
 0, don't sync.  Default: 0.
 .TP

+.BI fdatasync \fR=\fPint
+Like \fBfsync\fR, but uses \fBfdatasync\fR\|(2) instead to only sync the
+data parts of the file. Default: 0.
+.TP

 .BI overwrite \fR=\fPbool
 If writing, setup the file first and do overwrites.  Default: false.
 .TP
 .BI overwrite \fR=\fPbool
 If writing, setup the file first and do overwrites.  Default: false.
 .TP


@@ -508,6 +512,15 @@ the system must have free huge pages allocated.  \fBmmaphuge\fR also needs to
 have hugetlbfs mounted, and \fIfile\fR must point there.
 .RE
 .TP
 have hugetlbfs mounted, and \fIfile\fR must point there.
 .RE
 .TP

+.BI iomem_align \fR=\fPint
+This indiciates the memory alignment of the IO memory buffers. Note that the
+given alignment is applied to the first IO unit buffer, if using \fBiodepth\fR
+the alignment of the following buffers are given by the \fBbs\fR used. In
+other words, if using a \fBbs\fR that is a multiple of the page sized in the
+system, all buffers will be aligned to this value. If using a \fBbs\fR that
+is not page aligned, the alignment of subsequent IO memory buffers is the
+sum of the \fBiomem_align\fR and \fBbs\fR used.
+.TP

 .BI hugepage\-size \fR=\fPint
 Defines the size of a huge page.  Must be at least equal to the system setting.
 Should be a multiple of 1MiB. Default: 4MiB.
 .BI hugepage\-size \fR=\fPint
 Defines the size of a huge page.  Must be at least equal to the system setting.
 Should be a multiple of 1MiB. Default: 4MiB.


@@ -531,7 +544,9 @@ If true, the files are not created until they are opened for IO by the job.
 .BI pre_read \fR=\fPbool
 If this is given, files will be pre-read into memory before starting the given
 IO operation. This will also clear the \fR \fBinvalidate\fR flag, since it is
 .BI pre_read \fR=\fPbool
 If this is given, files will be pre-read into memory before starting the given
 IO operation. This will also clear the \fR \fBinvalidate\fR flag, since it is

-pointless to pre-read and then drop the cache.
+pointless to pre-read and then drop the cache. This will only work for IO
+engines that are seekable, since they allow you to read the same data
+multiple times. Thus it will not work on eg network or splice IO.

 .TP
 .BI unlink \fR=\fPbool
 Unlink job files when done.  Default: false.
 .TP
 .BI unlink \fR=\fPbool
 Unlink job files when done.  Default: false.


@@ -583,6 +598,16 @@ Write the verification header for this number of bytes, which should divide
 If true, exit the job on the first observed verification failure.  Default:
 false.
 .TP
 If true, exit the job on the first observed verification failure.  Default:
 false.
 .TP

+.BI verify_async \fR=\fPint
+Fio will normally verify IO inline from the submitting thread. This option
+takes an integer describing how many async offload threads to create for IO
+verification instead, causing fio to offload the duty of verifying IO contents
+to one or more separate threads.
+.TP
+.BI verify_async_cpus \fR=\fPstr
+Tell fio to set the given CPU affinity on the async IO verification threads.
+See \fBcpus_allowed\fP for the format used.
+.TP

 .B stonewall
 Wait for preceeding jobs in the job file to exit before starting this one.
 \fBstonewall\fR implies \fBnew_group\fR.
 .B stonewall
 Wait for preceeding jobs in the job file to exit before starting this one.
 \fBstonewall\fR implies \fBnew_group\fR.