block: bump BLK_DEF_MAX_SECTORS to 2560

A value of 2560 (1280k) will accommodate a 10-data-disk stripe write with chunk size 128k. In the testing I've done using iozone, fio, and aio-stress across a number of different storage devices, a value of 1280 does not show a big performance difference from 512, but will hopefully help software RAID setups using SATA disks, as reported by Christoph. NOTE: drivers/block/aoe/aoeblk.c sets its own max_hw_sectors_kb to BLK_DEF_MAX_SECTORS. So, this patch essentially changes aeoblk to Use a larger maximum sector size, and I did not test this. Signed-off-by: Jeff Moyer <[email protected]> Signed-off-by: Jens Axboe <[email protected]>
kyagi · Aug 18, 2015 · d2be537 · d2be537
1 parent 30e2bc0
commit d2be537
Showing 1 changed file with 1 addition and 1 deletion.
diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h
@@ -1132,7 +1132,7 @@ extern int blk_verify_command(unsigned char *cmd, fmode_t has_write_perm);
 enum blk_default_limits {
 	BLK_MAX_SEGMENTS	= 128,
 	BLK_SAFE_MAX_SECTORS	= 255,
-	BLK_DEF_MAX_SECTORS	= 1024,
+	BLK_DEF_MAX_SECTORS	= 2560,
 	BLK_MAX_SEGMENT_SIZE	= 65536,
 	BLK_SEG_BOUNDARY_MASK	= 0xFFFFFFFFUL,
 };