Add documentation for verify_backlog and verify_backlog_batch

Signed-off-by: Jens Axboe <jaxboe@fusionio.com>

diff --git a/HOWTO b/HOWTO
index 19304aefc87d92bc6fd17a3fd28f6768c79f8550..d320ab3852dbc69942f69ddde8bbacd0aab127ce 100644 (file)
--- a/HOWTO
+++ b/HOWTO
@@ -899,6 +899,22 @@ verify_async=int   Fio will normally verify IO inline from the submitting
 verify_async_cpus=str  Tell fio to set the given CPU affinity on the
                async IO verification threads. See cpus_allowed for the
                format used.
 verify_async_cpus=str  Tell fio to set the given CPU affinity on the
                async IO verification threads. See cpus_allowed for the
                format used.

+
+verify_backlog=int     Fio will normally verify the written contents of a
+               job that utilizes verify once that job has completed. In
+               other words, everything is written then everything is read
+               back and verified. You may want to verify continually
+               instead for a variety of reasons. Fio stores the meta data
+               associated with an IO block in memory, so for large
+               verify workloads, quite a bit of memory would be used up
+               holding this meta data. If this option is enabled, fio
+               will verify the previously written blocks before continuing
+               to write new ones.
+
+verify_backlog_batch=int       Control how many blocks fio will verify
+               if verify_backlog is set. If not set, will default to
+               the value of verify_backlog (meaning the entire queue
+               is read back and verified).

                
 stonewall      Wait for preceeding jobs in the job file to exit, before
                starting this one. Can be used to insert serialization
                
 stonewall      Wait for preceeding jobs in the job file to exit, before
                starting this one. Can be used to insert serialization

diff --git a/fio.1 b/fio.1
index ac729df5c895381114acb80eea91c6670a7405ae..a42eb98eb1feca84c5442a36bbbb03aa21778e99 100644 (file)
--- a/fio.1
+++ b/fio.1
@@ -653,6 +653,20 @@ allows them to have IO in flight while verifies are running.
 Tell fio to set the given CPU affinity on the async IO verification threads.
 See \fBcpus_allowed\fP for the format used.
 .TP
 Tell fio to set the given CPU affinity on the async IO verification threads.
 See \fBcpus_allowed\fP for the format used.
 .TP

+.BI verify_backlog \fR=\fPint
+Fio will normally verify the written contents of a job that utilizes verify
+once that job has completed. In other words, everything is written then
+everything is read back and verified. You may want to verify continually
+instead for a variety of reasons. Fio stores the meta data associated with an
+IO block in memory, so for large verify workloads, quite a bit of memory would
+be used up holding this meta data. If this option is enabled, fio will verify
+the previously written blocks before continuing to write new ones.
+.TP
+.BI verify_backlog_batch \fR=\fPint
+Control how many blocks fio will verify if verify_backlog is set. If not set,
+will default to the value of \fBverify_backlog\fR (meaning the entire queue is
+read back and verified).
+.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.