From ba0ffdd8ce48ad7f7e85191cd29f9674caca3745 Mon Sep 17 00:00:00 2001 From: Jens Axboe Date: Wed, 6 Oct 2021 12:01:07 -0600 Subject: block: bump max plugged deferred size from 16 to 32 Particularly for NVMe with efficient deferred submission for many requests, there are nice benefits to be seen by bumping the default max plug count from 16 to 32. This is especially true for virtualized setups, where the submit part is more expensive. But can be noticed even on native hardware. Reduce the multiple queue factor from 4 to 2, since we're changing the default size. While changing it, move the defines into the block layer private header. These aren't values that anyone outside of the block layer uses, or should use. Signed-off-by: Jens Axboe --- block/blk.h | 6 ++++++ 1 file changed, 6 insertions(+) (limited to 'block/blk.h') diff --git a/block/blk.h b/block/blk.h index 7aaccbc26db4..019c50a140ba 100644 --- a/block/blk.h +++ b/block/blk.h @@ -224,6 +224,12 @@ bool blk_bio_list_merge(struct request_queue *q, struct list_head *list, void blk_account_io_start(struct request *req); void blk_account_io_done(struct request *req, u64 now); +/* + * Plug flush limits + */ +#define BLK_MAX_REQUEST_COUNT 32 +#define BLK_PLUG_FLUSH_SIZE (128 * 1024) + /* * Internal elevator interface */ -- cgit v1.2.3