From mboxrd@z Thu Jan 1 00:00:00 1970 From: keith.busch@intel.com (Keith Busch) Date: Wed, 24 May 2017 07:21:42 -0400 Subject: Getting rid of nvme's pci watchdog timer? In-Reply-To: <20170524094219.GB17483@lst.de> References: <20170524094219.GB17483@lst.de> Message-ID: <20170524112141.GA13742@localhost.localdomain> On Wed, May 24, 2017@11:42:19AM +0200, Christoph Hellwig wrote: > an idle controller all the time seems pretty useful to me. I don't > really understand the need for the watchdog fully as it predates my > involvement, but I vaguely remember discussion the issue with Keith > a while ago, so he might be able to help. This was originally added to the driver's health check kthread to keep a pulse on the devices, but I think it's causing more harm than good. The hotplug races are bad enough, and this power savings killer is yet another reason to remove it. I'm in favor of removing the watchdog timer and moving the status check to the timeout callback so we verify health only when we have a reason to believe something is wrong.