From mboxrd@z Thu Jan 1 00:00:00 1970 From: keith.busch@linux.intel.com (Keith Busch) Date: Thu, 17 May 2018 09:06:54 -0600 Subject: [PATCH] nvme: remove cq check after submission In-Reply-To: References: <20180516212010.GC20223@localhost.localdomain> <20180517065049.GA30079@infradead.org> Message-ID: <20180517150654.GE22063@localhost.localdomain> On Thu, May 17, 2018@08:16:17AM -0600, Jens Axboe wrote: > On 5/17/18 12:50 AM, Christoph Hellwig wrote: > > On Wed, May 16, 2018@03:20:10PM -0600, Keith Busch wrote: > >> On Wed, May 16, 2018@01:58:08PM -0600, Jens Axboe wrote: > >>> We always check the completion queue after submitting, but in my testing > >>> this isn't a win even on DRAM/xpoint devices. In some cases it's > >>> actually worse. Kill it. > >> > >> Right, this was on my todo list. Agreed it's not helping anything. > >> Applied to nvme-4.18. > > > > While I agree in general didn't we have a case where this caused a > > regression last time it came up? Not that I'd complain if it goes > > away.. > > Not that I'm aware of. I've been running with this patch for quite > a while, while doing some work on polling. Yah, I mentioned a few months back there appeared to be a problem with removing this, but I was mistaken. I just didn't get back around to doing this.