Merge branch 'master' of ssh://git.kernel.dk/data/git/fio

[fio.git] / README

diff --git a/README b/README
index e933bd55ef356a4eadebfc7bd1a9345ee094fd95..ea8f5ef8e22c47462abafae9faf53e03509bc24f 100644 (file)
--- a/README
+++ b/README
@@ -57,6 +57,19 @@ $ make -f Makefile.Freebsd && make -f Makefile.FreeBSD install
 Likewise with OpenSolaris, use the Makefile.solaris to compile there.
 This might change in the future if I opt for an autoconf type setup.
 
+If your compile fails with an error like this:
+
+    CC gettime.o
+In file included from fio.h:23,
+                 from gettime.c:8:
+os/os.h:15:20: error: libaio.h: No such file or directory
+In file included from gettime.c:8:
+fio.h:119: error: field 'iocb' has incomplete type
+make: *** [gettime.o] Error 1
+
+Check that you have the libaio development package installed. On RPM
+based distros, it's typically called libaio-devel.
+
 
 Command line
 ------------
@@ -75,6 +88,8 @@ $ fio
        --readonly      Turn on safety read-only checks, preventing writes
        --eta=when      When ETA estimate should be printed
                        May be "always", "never" or "auto"
+       --section=name  Only run specified section in job file
+       --alloc-size=kb Set smalloc pool to this size in kb (def 1024)
 
 
 Any parameters following the options will be assumed to be job files,
@@ -98,11 +113,27 @@ options in fio. Currently the options are:
        blktrace        Dump info related to blktrace setup
        verify          Dump info related to IO verification
        all             Enable all debug options
+       random          Dump info related to random offset generation
+       parse           Dump info related to option matching and parsing
+       diskutil        Dump info related to disk utilization updates
        ? or help       Show available debug options.
 
 You can specify as many as you want, eg --debug=file,mem will enable
 file and memory debugging.
 
+The section switch is meant to make it easier to ship a bigger job file
+instead of several smaller ones. Say you define a job file with light,
+moderate, and heavy parts. Then you can ask fio to run the given part
+only by giving it a --section=heavy command line option. The section
+option only applies to job sections, the reserved 'global' section is
+always parsed and taken into account.
+
+Fio has an internal allocator for shared memory called smalloc. It
+allocates shared structures from this pool. The pool defaults to 1024k
+in size, and can grow to 32 pools. If running large jobs with randommap
+enabled it can run out of memory, in which case the --alloc-size switch
+is handy for starting with a larger pool size.
+
 
 Job file
 --------