Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751257AbaLCAmv (ORCPT ); Tue, 2 Dec 2014 19:42:51 -0500 Received: from cantor2.suse.de ([195.135.220.15]:47125 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750833AbaLCAmu (ORCPT ); Tue, 2 Dec 2014 19:42:50 -0500 From: Mel Gorman To: Andrew Morton , Michael Kerrisk Cc: Linux-MM , LKML , Mel Gorman Subject: [PATCH 0/2] Improve documentation of FADV_DONTNEED behaviour Date: Wed, 3 Dec 2014 00:42:45 +0000 Message-Id: <1417567367-9298-1-git-send-email-mgorman@suse.de> X-Mailer: git-send-email 2.1.2 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Partial page discard requests are ignored and the documentation on why this is correct behaviour sucks. A readahead patch looked like a "regression" to a random IO storage benchmark because posix_fadvise() was used incorrectly to force IO requests to go to disk. In reality, the benchmark sucked but it was non-obvious why. Patch 1 updates the kernel comment in case someone "fixes" either readahead or fadvise for inappropriate reasons. Patch 2 updates the relevant man page on the rough off chance that application developers do not read kernel source comments. -- 2.1.2 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/