The hpsa firmware will bypass the cache for any request larger than 1MB, so we should cap the request size to avoid any performance degradation in SLE12-SP2. This degradation is caused from d2be537c3ba3568acd79cd178327b842e60d035e, which changed max_sectors_kb to 1280k, but the hardware is able to work fine with it, so the true fix should be from hpsa driver. References: bsc#1025461 Signed-off-by: Yadan Fan <ydfan@xxxxxxxx> --- drivers/scsi/hpsa.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/scsi/hpsa.c b/drivers/scsi/hpsa.c index 73daace478cb..b4c0bbea680c 100644 --- a/drivers/scsi/hpsa.c +++ b/drivers/scsi/hpsa.c @@ -952,7 +952,7 @@ static struct scsi_host_template hpsa_driver_template = { #endif .sdev_attrs = hpsa_sdev_attrs, .shost_attrs = hpsa_shost_attrs, - .max_sectors = 8192, + .max_sectors = 1024, .no_write_same = 1, }; -- 2.12.3