README: add hint on missing libaio-devel package

[fio.git] / README

diff --git a/README b/README
index 7d6262ec8eb777260c708b1bed343ff3a0b1c2ed..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
 ------------
@@ -76,6 +89,7 @@ $ fio
        --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,
@@ -114,6 +128,12 @@ 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
 --------