From mboxrd@z Thu Jan 1 00:00:00 1970 From: keith.busch@intel.com (Keith Busch) Date: Tue, 5 Apr 2016 15:54:54 +0000 Subject: [PATCH 0/2] Block: Give option to force io polling In-Reply-To: <20160405123832.GA27788@infradead.org> References: <1459455554-2794-1-git-send-email-jonathan.derrick@intel.com> <20160405123832.GA27788@infradead.org> Message-ID: <20160405155453.GB12625@localhost.localdomain> On Tue, Apr 05, 2016@05:38:32AM -0700, Christoph Hellwig wrote: > On Thu, Mar 31, 2016@02:19:12PM -0600, Jon Derrick wrote: > > In 4.6, enabling io polling in direct-io was switched to a per-io flag. > > This had an unintended result of giving a significant difference when > > doing benchmarks between 4.5 and 4.6, using fio's sync engine. > > Only if you manually enabled polling beforehand. I really don't see > how this is going to be useful for actual applications vs benchmarks, > so I'll need more convincing arguments. I think it's more about providing opt-in control to make the low-latency benefit reachable to users with existing programs.