[BLOCK] Don't pin lots of memory in mempools
Currently we scale the mempool sizes depending on memory installed
in the machine, except for the bio pool itself which sits at a fixed
256 entry pre-allocation.
There's really no point in "optimizing" this OOM path, we just need
enough preallocated to make progress. A single unit is enough, lets
scale it down to 2 just to be on the safe side.
This patch saves ~150kb of pinned kernel memory on a 32-bit box.
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
diff --git a/drivers/md/dm-io.c b/drivers/md/dm-io.c
index 4eb73d3..8bdc8a8 100644
--- a/drivers/md/dm-io.c
+++ b/drivers/md/dm-io.c
@@ -60,7 +60,7 @@
if (!_io_pool)
return -ENOMEM;
- _bios = bioset_create(16, 16, 4);
+ _bios = bioset_create(16, 16);
if (!_bios) {
mempool_destroy(_io_pool);
_io_pool = NULL;