make sure __rand_0_1 does not return 0.0

[fio.git] / fio.1

diff --git a/fio.1 b/fio.1
index 3bd3318219eef54b9ee55ca2d0179378c2f681a9..99d9f9e07e63a7ccb2c6462bef9e70843ebc82a0 100644 (file)
--- a/fio.1
+++ b/fio.1
@@ -21,8 +21,10 @@ list all available tracing options.
 Write output to \fIfilename\fR.
 .TP
 .BI \-\-output-format \fR=\fPformat
 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.
+Set the reporting format to \fInormal\fR, \fIterse\fR, \fIjson\fR, or
+\fIjson+\fR. Multiple formats can be selected, separate by a comma. \fIterse\fR
+is a CSV based format. \fIjson+\fR is like \fIjson\fR, except it adds a full
+dump of the latency buckets.

 .TP
 .BI \-\-runtime \fR=\fPruntime
 Limit run time to \fIruntime\fR seconds.
 .TP
 .BI \-\-runtime \fR=\fPruntime
 Limit run time to \fIruntime\fR seconds.


@@ -286,7 +288,7 @@ Random trim (Linux block devices only).
 .B rw, readwrite
 Mixed sequential reads and writes.
 .TP
 .B rw, readwrite
 Mixed sequential reads and writes.
 .TP

-.B randrw 
+.B randrw

 Mixed random reads and writes.
 .TP
 .B trimwrite
 Mixed random reads and writes.
 .TP
 .B trimwrite


@@ -656,8 +658,8 @@ IO engine that does regular EXT4_IOC_MOVE_EXT ioctls to simulate defragment acti
 request to DDIR_WRITE event
 .TP
 .B rbd
 request to DDIR_WRITE event
 .TP
 .B rbd

-IO engine supporting direct access to Ceph Rados Block Devices (RBD) via librbd 
-without the need to use the kernel rbd driver. This ioengine defines engine specific 
+IO engine supporting direct access to Ceph Rados Block Devices (RBD) via librbd
+without the need to use the kernel rbd driver. This ioengine defines engine specific

 options.
 .TP
 .B gfapi
 options.
 .TP
 .B gfapi


@@ -748,7 +750,7 @@ we simply do polling.
 .TP
 .BI iodepth_low \fR=\fPint
 Low watermark indicating when to start filling the queue again.  Default:
 .TP
 .BI iodepth_low \fR=\fPint
 Low watermark indicating when to start filling the queue again.  Default:

-\fBiodepth\fR. 
+\fBiodepth\fR.

 .TP
 .BI io_submit_mode \fR=\fPstr
 This option controls how fio submits the IO to the IO engine. The default is
 .TP
 .BI io_submit_mode \fR=\fPstr
 This option controls how fio submits the IO to the IO engine. The default is


@@ -961,6 +963,10 @@ size is used as the metric.
 If this rate of I/O is not met, the job will exit. The same format as \fBrate\fR
 is used for read vs write separation.
 .TP
 If this rate of I/O is not met, the job will exit. The same format as \fBrate\fR
 is used for read vs write separation.
 .TP

+.BI rate_poisson \fR=\fPbool
+When rate limited, try to simulate request flow under Poisson process (instead
+of even distribution). Default: false.
+.TP

 .BI ratecycle \fR=\fPint
 Average bandwidth for \fBrate\fR and \fBratemin\fR over this number of
 milliseconds.  Default: 1000ms.
 .BI ratecycle \fR=\fPint
 Average bandwidth for \fBrate\fR and \fBratemin\fR over this number of
 milliseconds.  Default: 1000ms.


@@ -1278,8 +1284,8 @@ only N blocks before verifying these blocks.
 .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
 .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).  If \fBverify_backlog_batch\fR is less than 
-\fBverify_backlog\fR then not all blocks will be verified,  if 
+read back and verified).  If \fBverify_backlog_batch\fR is less than
+\fBverify_backlog\fR then not all blocks will be verified,  if

 \fBverify_backlog_batch\fR is larger than \fBverify_backlog\fR,  some blocks
 will be verified more than once.
 .TP
 \fBverify_backlog_batch\fR is larger than \fBverify_backlog\fR,  some blocks
 will be verified more than once.
 .TP


@@ -1318,7 +1324,7 @@ Start a new reporting group.  If not given, all jobs in a file will be part
 of the same reporting group, unless separated by a stonewall.
 .TP
 .BI numjobs \fR=\fPint
 of the same reporting group, unless separated by a stonewall.
 .TP
 .BI numjobs \fR=\fPint

-Number of clones (processes/threads performing the same workload) of this job.  
+Number of clones (processes/threads performing the same workload) of this job.

 Default: 1.
 .TP
 .B group_reporting
 Default: 1.
 .TP
 .B group_reporting


@@ -1511,8 +1517,8 @@ errors for given error type is separated with ':'.
 Error may be symbol ('ENOSPC', 'ENOMEM') or an integer.
 .br
 Example: ignore_error=EAGAIN,ENOSPC:122 .
 Error may be symbol ('ENOSPC', 'ENOMEM') or an integer.
 .br
 Example: ignore_error=EAGAIN,ENOSPC:122 .

-.br    
-This option will ignore EAGAIN from READ, and ENOSPC and 122(EDQUOT) from WRITE. 
+.br
+This option will ignore EAGAIN from READ, and ENOSPC and 122(EDQUOT) from WRITE.

 .TP
 .BI error_dump \fR=\fPbool
 If set dump every error even if it is non fatal, true by default. If disabled
 .TP
 .BI error_dump \fR=\fPbool
 If set dump every error even if it is non fatal, true by default. If disabled


@@ -1685,7 +1691,7 @@ Set the TCP maximum segment size (TCP_MAXSEG).
 File will be used as a block donor (swap extents between files)
 .TP
 .BI (e4defrag,inplace) \fR=\fPint
 File will be used as a block donor (swap extents between files)
 .TP
 .BI (e4defrag,inplace) \fR=\fPint

-Configure donor file block allocation strategy         
+Configure donor file block allocation strategy

 .RS
 .BI 0(default) :
 Preallocate donor's file on init
 .RS
 .BI 0(default) :
 Preallocate donor's file on init


@@ -1949,7 +1955,7 @@ Disk utilization (1 for each disk used):
 .P
 Error Info (dependent on continue_on_error, default off):
 .RS
 .P
 Error Info (dependent on continue_on_error, default off):
 .RS

-.B total # errors, first error code 
+.B total # errors, first error code

 .RE
 .P
 .B text description (if provided in config - appears on newline)
 .RE
 .P
 .B text description (if provided in config - appears on newline)


@@ -2016,7 +2022,7 @@ fio \-\-client=server \-\-remote-config /path/to/file.fio
 Then fio will open this local (to the server) job file instead
 of being passed one from the client.
 
 Then fio will open this local (to the server) job file instead
 of being passed one from the client.
 

-If you have many servers (example: 100 VMs/containers), you can input a pathname 
+If you have many servers (example: 100 VMs/containers), you can input a pathname

 of a file containing host IPs/names as the parameter value for the \-\-client option.
 For example, here is an example "host.list" file containing 2 hostnames:
 
 of a file containing host IPs/names as the parameter value for the \-\-client option.
 For example, here is an example "host.list" file containing 2 hostnames:
 


@@ -2032,8 +2038,8 @@ In this mode, you cannot input server-specific parameters or job files, and all
 servers receive the same job file.
 
 In order to enable fio \-\-client runs utilizing a shared filesystem from multiple hosts,
 servers receive the same job file.
 
 In order to enable fio \-\-client runs utilizing a shared filesystem from multiple hosts,

-fio \-\-client now prepends the IP address of the server to the filename. For example, 
-if fio is using directory /mnt/nfs/fio and is writing filename fileio.tmp, 
+fio \-\-client now prepends the IP address of the server to the filename. For example,
+if fio is using directory /mnt/nfs/fio and is writing filename fileio.tmp,

 with a \-\-client hostfile
 containing two hostnames h1 and h2 with IP addresses 192.168.10.120 and 192.168.10.121, then
 fio will create two files:
 with a \-\-client hostfile
 containing two hostnames h1 and h2 with IP addresses 192.168.10.120 and 192.168.10.121, then
 fio will create two files:


@@ -2057,4 +2063,3 @@ See \fBREADME\fR.
 For further documentation see \fBHOWTO\fR and \fBREADME\fR.
 .br
 Sample jobfiles are available in the \fBexamples\fR directory.
 For further documentation see \fBHOWTO\fR and \fBREADME\fR.
 .br
 Sample jobfiles are available in the \fBexamples\fR directory.

-