Allow explicit setting of a number of files

[fio.git] / HOWTO

diff --git a/HOWTO b/HOWTO
index d1a3ad1e3291bb5b23555ec5c388c2ab48185322..5df2607e874a35fa131db5f36a0095af2dfe917a 100644 (file)
--- a/HOWTO
+++ b/HOWTO
@@ -205,7 +205,11 @@ filename=str       Fio normally makes up a filename based on the job name,
                files between threads in a job or several jobs, specify
                a filename for each of them to override the default. If
                the ioengine used is 'net', the filename is the host and
-               port to connect to in the format of =host:port.
+               port to connect to in the format of =host:port. If the
+               ioengine is file based, you can specify a number of files
+               by seperating the names with a ':' colon. So if you wanted
+               a job to open /dev/sda and /dev/sdb as the two working files,
+               you would use filename=/dev/sda:/dev/sdb
 
 rw=str         Type of io pattern. Accepted values are:
 
@@ -265,6 +269,11 @@ file_service_type=str  Defines how fio decides which file from a job to
                        roundrobin  Round robin over open files. This
                                is the default.
 
+               The string can have a number appended, indicating how
+               often to switch to a new file. So if option random:4 is
+               given, fio will switch to a new random file after 4 ios
+               have been issued.
+
 ioengine=str   Defines how the job issues io to the file. The following
                types are defined:
 
@@ -301,6 +310,12 @@ ioengine=str       Defines how the job issues io to the file. The following
                                or receive, if the latter only the port
                                argument is used.
 
+                       cpu     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
+                               85% of the CPU.
+
                        external Prefix to specify loading an external
                                IO engine object file. Append the engine
                                filename, eg ioengine=external:/tmp/foo.o