Yes, we normally use 128, as this is the value best suited for our RAID systems. After upgrading the software we saw a clear performance reduction that was caused by the bug.
With the fix everything works fine again. Thank you, Bodo > -----Original Message----- > From: James Smart [mailto:[email protected]] > Sent: Friday, May 29, 2015 4:05 PM > To: Strösser, Bodo; [email protected] > Subject: Re: [PATCH] lpfc: in sli3 use configured sg_seg_cnt for sg_tablesize > > Bodo, > > This is a valid fix. Thank you. > > I assume you were changing the driver module parameter to up the SG > count ? without the fix we would have been capped at 64 sges. > > -- james > > Reviewed-By: James Smart <[email protected]> > > > > On 5/29/2015 8:22 AM, [email protected] wrote: > > Hi James, > > > > We had some performance problems with RAID systems connected to LPe12k. > > AFAICS, the reason is a small bug in lpfc.ko, causing the IO-size to > > be smaller than expected. > > > > The patch below fixes it for us. > > > > Please CC me, I'm not on the list. > > > > Best regards > > Bodo > > > > > > ------------------------------------------------------ > > > > From: Bodo Stroesser <[email protected]> > > Date: Fri, 29 May 2015 13:34:19 +0200 > > Subject: [PATCH] lpfc: in sli3 use configured sg_seg_cnt for sg_tablesize > > > > Currently the module parameter lpfc_sg_seg_count does not have effect > > for sli3 devices. > > > > In lpfc_sli_driver_resource_setup(), which is used for sli3, the code > > writes the configured sg_seg_cnt into lpfc_template.sg_tablesize. > > But lpfc_template is the template used for sli4 only. Thus the value should > > correctly be written to lpfc_template_s3->sg_tablesize. > > > > This patch is for kernel 4.1-rc5, but is tested with lpfc 10.2.405.26 only. > > > > Signed-off-by: Bodo Stroesser <[email protected]> > > --- > > > > --- a/drivers/scsi/lpfc/lpfc_init.c 2015-05-29 10:19:02.000000000 +0200 > > +++ b/drivers/scsi/lpfc/lpfc_init.c 2015-05-29 10:19:56.000000000 +0200 > > @@ -4988,7 +4988,7 @@ lpfc_sli_driver_resource_setup(struct lp > > > > /* Initialize the host templates the configured values. */ > > lpfc_vport_template.sg_tablesize = phba->cfg_sg_seg_cnt; > > - lpfc_template.sg_tablesize = phba->cfg_sg_seg_cnt; > > + lpfc_template_s3.sg_tablesize = phba->cfg_sg_seg_cnt; > > > > /* There are going to be 2 reserved BDEs: 1 FCP cmnd + 1 FCP rsp */ > > if (phba->cfg_enable_bg) { -- To unsubscribe from this list: send the line "unsubscribe linux-scsi" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
