splice: fix problem with current mainline kernels

[fio.git] / HOWTO

diff --git a/HOWTO b/HOWTO
index 2fbbc1d2150e3e70a1512f83ea45b54c44c45977..5d757b2d17f716d3b143171cf716d1c8fba6e2a0 100644 (file)
--- a/HOWTO
+++ b/HOWTO
@@ -170,7 +170,8 @@ Some parameters take an option of a given type, such as an integer or
 a string. The following types are used:
 
 str    String. This is a sequence of alpha characters.
 a string. The following types are used:
 
 str    String. This is a sequence of alpha characters.

-int    Integer. A whole number value, can be negative.
+int    Integer. A whole number value, can be negative. If prefixed with
+       0x, the integer is assumed to be of base 16 (hexidecimal).

 siint  SI integer. A whole number value, which may contain a postfix
        describing the base of the number. Accepted postfixes are k/m/g,
        meaning kilo, mega, and giga. So if you want to specify 4096,
 siint  SI integer. A whole number value, which may contain a postfix
        describing the base of the number. Accepted postfixes are k/m/g,
        meaning kilo, mega, and giga. So if you want to specify 4096,


@@ -346,7 +347,7 @@ ioengine=str        Defines how the job issues io to the file. The following
                        netsplice Like net, but uses splice/vmsplice to
                                map data and send/receive.
 
                        netsplice Like net, but uses splice/vmsplice to
                                map data and send/receive.
 

-                       cpu     Doesn't transfer any data, but burns CPU
+                       cpuio   Doesn't transfer any data, but burns CPU

                                cycles according to the cpuload= and
                                cpucycle= options. Setting cpuload=85
                                will cause that job to do nothing but burn
                                cycles according to the cpuload= and
                                cpucycle= options. Setting cpuload=85
                                will cause that job to do nothing but burn


@@ -568,6 +569,9 @@ loops=int   Run the specified number of iterations of this job. Used
                to repeat the same workload a given number of times. Defaults
                to 1.
 
                to repeat the same workload a given number of times. Defaults
                to 1.
 

+do_verify=bool Run the verify phase after a write phase. Only makes sense if
+               verify is set. Defaults to 1.
+

 verify=str     If writing to a file, fio can verify the file contents
                after each iteration of the job. The allowed values are:
 
 verify=str     If writing to a file, fio can verify the file contents
                after each iteration of the job. The allowed values are:
 


@@ -587,6 +591,23 @@ verify=str If writing to a file, fio can verify the file contents
                        crc7    Use a crc7 sum of the data area and store
                                it in the header of each block.
 
                        crc7    Use a crc7 sum of the data area and store
                                it in the header of each block.
 

+                       sha512  Use sha512 as the checksum function.
+
+                       sha256  Use sha256 as the checksum function.
+
+                       meta    Write extra information about each io
+                               (timestamp, block number etc.). The block
+                               number is verified.
+
+                       pattern Fill the IO buffers with a specific pattern,
+                               that we can use to verify. Depending on the
+                               width of the pattern, fio will fill 1/2/3/4
+                               bytes of the buffer at the time. The pattern
+                               cannot be larger than a 32-bit quantity. The
+                               given pattern is given as a postfix to this
+                               option, ala: verify=pattern:0x5a. It accepts
+                               both hex and dec values.
+

                        null    Only pretend to verify. Useful for testing
                                internals with ioengine=null, not for much
                                else.
                        null    Only pretend to verify. Useful for testing
                                internals with ioengine=null, not for much
                                else.


@@ -611,6 +632,11 @@ verify_interval=siint      Write the verification header at a finer granularity
                        than the blocksize. It will be written for chunks the
                        size of header_interval. blocksize should divide this
                        evenly.
                        than the blocksize. It will be written for chunks the
                        size of header_interval. blocksize should divide this
                        evenly.

+
+verify_fatal=bool      Normally fio will keep checking the entire contents
+               before quitting on a block verification failure. If this
+               option is set, fio will exit the job on the first observed
+               failure.

                
 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


@@ -730,7 +756,7 @@ Client1 (g=0): err= 0:
     slat (msec): min=    0, max=  136, avg= 0.03, stdev= 1.92
     clat (msec): min=    0, max=  631, avg=48.50, stdev=86.82
     bw (KiB/s) : min=    0, max= 1196, per=51.00%, avg=664.02, stdev=681.68
     slat (msec): min=    0, max=  136, avg= 0.03, stdev= 1.92
     clat (msec): min=    0, max=  631, avg=48.50, stdev=86.82
     bw (KiB/s) : min=    0, max= 1196, per=51.00%, avg=664.02, stdev=681.68

-  cpu        : usr=1.49%, sys=0.25%, ctx=7969
+  cpu        : usr=1.49%, sys=0.25%, ctx=7969, majf=0, minf=17

   IO depths    : 1=0.1%, 2=0.3%, 4=0.5%, 8=99.0%, 16=0.0%, 32=0.0%, >32=0.0%
      issued r/w: total=0/32768, short=0/0
      lat (msec): 2=1.6%, 4=0.0%, 10=3.2%, 20=12.8%, 50=38.4%, 100=24.8%,
   IO depths    : 1=0.1%, 2=0.3%, 4=0.5%, 8=99.0%, 16=0.0%, 32=0.0%, >32=0.0%
      issued r/w: total=0/32768, short=0/0
      lat (msec): 2=1.6%, 4=0.0%, 10=3.2%, 20=12.8%, 50=38.4%, 100=24.8%,


@@ -761,7 +787,9 @@ runt=               The runtime of that thread
                only really useful if the threads in this group are on the
                same disk, since they are then competing for disk access.
 cpu=           CPU usage. User and system time, along with the number
                only really useful if the threads in this group are on the
                same disk, since they are then competing for disk access.
 cpu=           CPU usage. User and system time, along with the number

-               of context switches this thread went through.
+               of context switches this thread went through, usage of
+               system and user time, and finally the number of major
+               and minor page faults.

 IO depths=     The distribution of io depths over the job life time. The
                numbers are divided into powers of 2, so for example the
                16= entries includes depths up to that value but higher
 IO depths=     The distribution of io depths over the job life time. The
                numbers are divided into powers of 2, so for example the
                16= entries includes depths up to that value but higher