| Message ID | 20170623094006.16807-1-ydfan@suse.com (mailing list archive) |
|---|---|
| State | Accepted |
| Headers | show |
On Fri, Jun 23, 2017 at 05:40:05PM +0800, Yadan Fan wrote: > 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 kernels later than v4.3 > > 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. > > Signed-off-by: Yadan Fan <ydfan@suse.com> > --- Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Don, > 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 kernels later than v4.3 I assume you guys are OK with this change?
Yadan, > 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 kernels later than v4.3 Applied to 4.13/scsi-fixes. Thanks!
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, };
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 kernels later than v4.3 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. Signed-off-by: Yadan Fan <ydfan@suse.com> --- Changes: Reduced SUSE distribution info and internal bug id reference. drivers/scsi/hpsa.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)