Add softrandommap and --alloc-size options
The softrandommap job option allows fio to continue if it cannot
allocate from the smalloc backing for the random map. Or the user
can specify --alloc-size with a size larger than the default of 1024k
to increase the size of the shared allocation pool.
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
diff --git a/README b/README
index 7d6262e..db8e672 100644
--- a/README
+++ b/README
@@ -76,6 +76,7 @@
--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 +115,12 @@
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
--------