[SCSI] pm8001: raise host can queue
This is a followup to a patch provided by Jack Wang on September 21 2011.
After increasing the CAN_QUEUE to 510 in pm8001 we discovered some performance
degredation from time to time. We needed to increase the MPI queue to
compensate and ensure we never hit that limit. We also needed to double
the margin to support event and administrivial commands that take from
the pool resulting in an occasional largely unproductive command completion
with soft error to the caller when the command pool is overloaded temporarily.
Signed-off-by: Mark Salyzyn <mark_salyzyn@xyratex.com>
Acked-by: Jack Wang <jack_wang@usish.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
diff --git a/drivers/scsi/pm8001/pm8001_defs.h b/drivers/scsi/pm8001/pm8001_defs.h
index 944afad..c3d20c8 100644
--- a/drivers/scsi/pm8001/pm8001_defs.h
+++ b/drivers/scsi/pm8001/pm8001_defs.h
@@ -66,9 +66,10 @@
/* driver compile-time configuration */
#define PM8001_MAX_CCB 512 /* max ccbs supported */
+#define PM8001_MPI_QUEUE 1024 /* maximum mpi queue entries */
#define PM8001_MAX_INB_NUM 1
#define PM8001_MAX_OUTB_NUM 1
-#define PM8001_CAN_QUEUE 128 /* SCSI Queue depth */
+#define PM8001_CAN_QUEUE 508 /* SCSI Queue depth */
/* unchangeable hardware details */
#define PM8001_MAX_PHYS 8 /* max. possible phys */