Return-Path: Received: from mailout4.samsung.com ([203.254.224.34]:23530 "EHLO mailout4.samsung.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727080AbeLJMwt (ORCPT ); Mon, 10 Dec 2018 07:52:49 -0500 From: Kanchan Joshi To: linux-ext4@vger.kernel.org, linux-fsdevel@vger.kernel.org Cc: tytso@mit.edu, adilger.kernel@dilger.ca, jack@suse.com, viro@zeniv.linux.org.uk, darrick.wong@oracle.com, axboe@kernel.dk, jrdr.linux@gmail.com, ebiggers@google.com, jooyoung.hwang@samsung.com, chur.lee@samsung.com, prakash.v@samsung.com, Kanchan Joshi Subject: [PATCH 0/2] fs,ext4,jbd2: Specifying write-hint for Ext4 journal Date: Mon, 10 Dec 2018 18:20:02 +0530 Message-id: <1544446204-5291-1-git-send-email-joshi.k@samsung.com> References: Sender: linux-ext4-owner@vger.kernel.org List-ID: For NAND-based SSDs, mixing of data with different life-time reduces efficiency of garbage-collection. During FS operations, series of journal updates will follow/precede series of data/meta updates, causing intermixing inside SSD. By passing a write-hint (a.k.a stream) with journal, its writes can be isolated from other meta/data writes, leading to performance/endurance benefit on multi-stream SSD. This is described in greater detail (along with results) in this "FAST 2018" paper - https://www.usenix.org/system/files/conference/fast18/fast18-rho.pdf This patch is split into two parts. First patch introduces APIs to send write-hint with buffer-head. Second one implement "journal_writehint" mount option (inspired from "journal_ioprio") in Ext4/JBD2. Kanchan Joshi (2): fs: introduce APIs to enable sending write-hint with buffer-head fs/ext4,jbd2: Add support for passing write-hint with journal. fs/buffer.c | 21 +++++++++++++++++++++ fs/ext4/super.c | 33 +++++++++++++++++++++++++++------ fs/jbd2/commit.c | 11 +++++++---- fs/jbd2/journal.c | 2 +- fs/jbd2/revoke.c | 2 +- include/linux/buffer_head.h | 3 +++ include/linux/jbd2.h | 7 +++++++ 7 files changed, 67 insertions(+), 12 deletions(-) -- 2.7.4