Mention default values for readwrite=/ioengine=/mem= in documentation

[fio.git] / HOWTO

diff --git a/HOWTO b/HOWTO
index ab25cb2796ddafeec8b375fe832c61825238fe81..ca1542d5fdf88b7fa0e6e607ab019a98c5d2d770 100644 (file)
--- a/HOWTO
+++ b/HOWTO
@@ -405,6 +405,7 @@ rw=str              Type of io pattern. Accepted values are:
                        trimwrite       Mixed trims and writes. Blocks will be
                                        trimmed first, then written to.
 
                        trimwrite       Mixed trims and writes. Blocks will be
                                        trimmed first, then written to.
 

+               Fio defaults to read if the option is not specified.

                For the mixed io types, the default is to split them 50/50.
                For certain types of io the result may still be skewed a bit,
                since the speed may be different. It is possible to specify
                For the mixed io types, the default is to split them 50/50.
                For certain types of io the result may still be skewed a bit,
                since the speed may be different. It is possible to specify


@@ -699,7 +700,8 @@ ioengine=str        Defines how the job issues io to the file. The following
                        sync    Basic read(2) or write(2) io. lseek(2) is
                                used to position the io location.
 
                        sync    Basic read(2) or write(2) io. lseek(2) is
                                used to position the io location.
 

-                       psync   Basic pread(2) or pwrite(2) io.
+                       psync   Basic pread(2) or pwrite(2) io. Default on all
+                               supported operating systems except for Windows.

 
                        vsync   Basic readv(2) or writev(2) IO.
 
 
                        vsync   Basic readv(2) or writev(2) IO.
 


@@ -717,6 +719,7 @@ ioengine=str        Defines how the job issues io to the file. The following
                        solarisaio Solaris native asynchronous io.
 
                        windowsaio Windows native asynchronous io.
                        solarisaio Solaris native asynchronous io.
 
                        windowsaio Windows native asynchronous io.

+                               Default on Windows.

 
                        mmap    File is memory mapped and data copied
                                to/from using memcpy(3).
 
                        mmap    File is memory mapped and data copied
                                to/from using memcpy(3).


@@ -1221,6 +1224,7 @@ mem=str           Fio can use various types of memory as the io unit buffer.
                The allowed values are:
 
                        malloc  Use memory from malloc(3) as the buffers.
                The allowed values are:
 
                        malloc  Use memory from malloc(3) as the buffers.

+                               Default memory type.

 
                        shm     Use shared memory as the buffers. Allocated
                                through shmget(2).
 
                        shm     Use shared memory as the buffers. Allocated
                                through shmget(2).