Martin, The firmware provided queue depth provides optimum performance in most of the cases/workloads. And this patch provides the option to the user to go with max queue_depth or with optimum queue_depth.
-Chandrakanth -----Original Message----- From: Martin K. Petersen [mailto:martin.peter...@oracle.com] Sent: Thursday, August 8, 2019 6:56 AM To: Chandrakanth Patil <chandrakanth.pa...@broadcom.com> Cc: linux-scsi@vger.kernel.org; kashyap.de...@broadcom.com; sumit.sax...@broadcom.com; kiran-kumar.kast...@broadcom.com; sankar.pa...@broadcom.com; sasikumar...@broadcom.com; shivasharan.srikanteshw...@broadcom.com; anand.lodn...@broadcom.com Subject: Re: [PATCH] megaraid_sas: change sdev queue depth max vs optimal Chandrakanth, > This patch provides the module parameter and sysfs interface to switch > between the firmware provided (optimal) queue depth and controller > queue depth (can_queue). This smells a bit like a don't-be-broken flag. Why isn't the firmware-provided value optimal? -- Martin K. Petersen Oracle Linux Engineering