From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1034678AbcIWOdR (ORCPT ); Fri, 23 Sep 2016 10:33:17 -0400 Received: from mail-cys01nam02on0066.outbound.protection.outlook.com ([104.47.37.66]:38070 "EHLO NAM02-CY1-obe.outbound.protection.outlook.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S966071AbcIWOdA (ORCPT ); Fri, 23 Sep 2016 10:33:00 -0400 Authentication-Results: spf=pass (sender IP is 63.163.107.21) smtp.mailfrom=sandisk.com; kernel.org; dkim=none (message not signed) header.d=none;kernel.org; dmarc=bestguesspass action=none header.from=sandisk.com; X-AuditID: 0ac94369-babff7000001694f-92-57e53acb46c2 Subject: Re: [dm-devel] [RFC][PATCH] dm: Remove dm_bufio_cond_resched() To: Peter Zijlstra , Thomas Gleixner References: <20160913084520.GA5012@twins.programming.kicks-ass.net> <20160913133959.GA22833@redhat.com> <20160919105325.GW5016@twins.programming.kicks-ass.net> <20160923073435.GL2794@worktop> CC: Mike Snitzer , Joe Thornber , , , Mikulas Patocka , Ingo Molnar , Alasdair Kergon From: Bart Van Assche Message-ID: <89c9d841-36c4-8b7e-544f-607cbdb2eec0@sandisk.com> Date: Fri, 23 Sep 2016 07:32:47 -0700 User-Agent: Mozilla/5.0 (X11; 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Most workloads also care about > latency to some extend. Lots of code has explicit cond_resched() and > doesn't worry. From a SLES11 system: $ grep PREEMPT_NONE /boot/config-3.0.101-0.47.67-default CONFIG_PREEMPT_NONE=y From a SLES12 system: $ grep CONFIG_PREEMPT_NONE /boot/config-4.4.16-56-default CONFIG_PREEMPT_NONE=y Bart.