From patchwork Mon Jul 23 17:22:05 2012 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Josef Bacik X-Patchwork-Id: 1228351 Return-Path: X-Original-To: patchwork-linux-btrfs@patchwork.kernel.org Delivered-To: patchwork-process-083081@patchwork1.kernel.org Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by patchwork1.kernel.org (Postfix) with ESMTP id 503033FD4F for ; Mon, 23 Jul 2012 17:17:15 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753993Ab2GWRRJ (ORCPT ); Mon, 23 Jul 2012 13:17:09 -0400 Received: from mx2.fusionio.com ([66.114.96.31]:41614 "EHLO mx2.fusionio.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753828Ab2GWRRH (ORCPT ); Mon, 23 Jul 2012 13:17:07 -0400 X-ASG-Debug-ID: 1343063826-0421b505a827900001-6jHSXT Received: from mail1.int.fusionio.com (mail1.int.fusionio.com [10.101.1.21]) by mx2.fusionio.com with ESMTP id DTAizbQobGpAGOPh (version=TLSv1 cipher=AES128-SHA bits=128 verify=NO) for ; Mon, 23 Jul 2012 11:17:06 -0600 (MDT) X-Barracuda-Envelope-From: JBacik@fusionio.com Received: from localhost (174.99.59.182) by mail.fusionio.com (10.101.1.19) with Microsoft SMTP Server (TLS) id 8.3.83.0; Mon, 23 Jul 2012 11:17:05 -0600 From: Josef Bacik To: Subject: [PATCH] Btrfs-progs: detect if the disk we are formatting is a ssd V2 Date: Mon, 23 Jul 2012 13:22:05 -0400 X-ASG-Orig-Subj: [PATCH] Btrfs-progs: detect if the disk we are formatting is a ssd V2 Message-ID: <1343064125-4023-1-git-send-email-jbacik@fusionio.com> X-Mailer: git-send-email 1.7.7.6 MIME-Version: 1.0 X-Barracuda-Connect: mail1.int.fusionio.com[10.101.1.21] X-Barracuda-Start-Time: 1343063826 X-Barracuda-Encrypted: AES128-SHA X-Barracuda-URL: http://10.101.1.181:8000/cgi-mod/mark.cgi X-Virus-Scanned: by bsmtpd at fusionio.com X-Barracuda-Spam-Score: 0.00 X-Barracuda-Spam-Status: No, SCORE=0.00 using global scores of TAG_LEVEL=1000.0 QUARANTINE_LEVEL=1000.0 KILL_LEVEL=9.0 tests= X-Barracuda-Spam-Report: Code version 3.2, rules version 3.2.2.103544 Rule breakdown below pts rule name description ---- ---------------------- -------------------------------------------------- Sender: linux-btrfs-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-btrfs@vger.kernel.org SSD's do not gain anything by having metadata DUP turned on. The underlying file system that is a part of all SSD's could easily map duplicate metadat blocks into the same erase block which effectively eliminates the benefit of duplicating the metadata on disk. So detect if we are formatting a single SSD drive and if we are do not use DUP. Thanks, Signed-off-by: Josef Bacik --- V1->V2: add explanation to man page and print a message if we default to single metadata in the case of an SSD. Makefile | 2 +- man/mkfs.btrfs.8.in | 5 +++- mkfs.c | 58 ++++++++++++++++++++++++++++++++++++++++++++++++-- 3 files changed, 60 insertions(+), 5 deletions(-) diff --git a/Makefile b/Makefile index 9694444..d827216 100644 --- a/Makefile +++ b/Makefile @@ -65,7 +65,7 @@ btrfsck: $(objects) btrfsck.o $(CC) $(CFLAGS) -o btrfsck btrfsck.o $(objects) $(LDFLAGS) $(LIBS) mkfs.btrfs: $(objects) mkfs.o - $(CC) $(CFLAGS) -o mkfs.btrfs $(objects) mkfs.o $(LDFLAGS) $(LIBS) + $(CC) $(CFLAGS) -o mkfs.btrfs $(objects) mkfs.o $(LDFLAGS) $(LIBS) -lblkid btrfs-debug-tree: $(objects) debug-tree.o $(CC) $(CFLAGS) -o btrfs-debug-tree $(objects) debug-tree.o $(LDFLAGS) $(LIBS) diff --git a/man/mkfs.btrfs.8.in b/man/mkfs.btrfs.8.in index fc2e1d2..dfa7996 100644 --- a/man/mkfs.btrfs.8.in +++ b/man/mkfs.btrfs.8.in @@ -46,7 +46,10 @@ Specify a label for the filesystem. .TP \fB\-m\fR, \fB\-\-metadata \fIprofile\fR Specify how metadata must be spanned across the devices specified. Valid -values are raid0, raid1, raid10 or single. +values are raid0, raid1, raid10, single or dup. Single device will have dup +set by default except in the case of SSDs which will default to single. This is +because SSDs can remap blocks internally so duplicate blocks could end up in the +same erase block which negates the benefits of doing metadata duplication. .TP \fB\-M\fR, \fB\-\-mixed\fR Mix data and metadata chunks together for more efficient space diff --git a/mkfs.c b/mkfs.c index dff5eb8..8816db8 100644 --- a/mkfs.c +++ b/mkfs.c @@ -37,6 +37,7 @@ #include #include #include +#include #include "kerncompat.h" #include "ctree.h" #include "disk-io.h" @@ -234,7 +235,7 @@ static int create_one_raid_group(struct btrfs_trans_handle *trans, static int create_raid_groups(struct btrfs_trans_handle *trans, struct btrfs_root *root, u64 data_profile, int data_profile_opt, u64 metadata_profile, - int metadata_profile_opt, int mixed) + int metadata_profile_opt, int mixed, int ssd) { u64 num_devices = btrfs_super_num_devices(&root->fs_info->super_copy); u64 allowed; @@ -245,8 +246,12 @@ static int create_raid_groups(struct btrfs_trans_handle *trans, * For mixed groups defaults are single/single. */ if (!metadata_profile_opt && !mixed) { + if (num_devices == 1 && ssd) + printf("Detected a SSD, turning off metadata " + "duplication. Mkfs with -m dup if you want to " + "force metadata duplication.\n"); metadata_profile = (num_devices > 1) ? - BTRFS_BLOCK_GROUP_RAID1 : BTRFS_BLOCK_GROUP_DUP; + BTRFS_BLOCK_GROUP_RAID1 : (ssd) ? 0: BTRFS_BLOCK_GROUP_DUP; } if (!data_profile_opt && !mixed) { data_profile = (num_devices > 1) ? @@ -1201,6 +1206,49 @@ static int zero_output_file(int out_fd, u64 size, u32 sectorsize) return ret; } +static int is_ssd(const char *file) +{ + char *devname; + blkid_probe probe; + char *dev; + char path[PATH_MAX]; + dev_t disk; + int fd; + char rotational; + + probe = blkid_new_probe_from_filename(file); + if (!probe) + return 0; + + /* + * We want to use blkid_devno_to_wholedisk() but it's broken for some + * reason on F17 at least so we'll do this trickery + */ + disk = blkid_probe_get_wholedisk_devno(probe); + devname = blkid_devno_to_devname(disk); + + dev = strrchr(devname, '/'); + dev++; + + snprintf(path, PATH_MAX, "/sys/block/%s/queue/rotational", dev); + + free(devname); + blkid_free_probe(probe); + + fd = open(path, O_RDONLY); + if (fd < 0) { + return 0; + } + + if (read(fd, &rotational, sizeof(char)) < sizeof(char)) { + close(fd); + return 0; + } + close(fd); + + return !atoi((const char *)&rotational); +} + int main(int ac, char **av) { char *file; @@ -1227,6 +1275,7 @@ int main(int ac, char **av) int data_profile_opt = 0; int metadata_profile_opt = 0; int nodiscard = 0; + int ssd = 0; char *source_dir = NULL; int source_dir_set = 0; @@ -1352,6 +1401,9 @@ int main(int ac, char **av) exit(1); } } + + ssd = is_ssd(file); + if (mixed) { if (metadata_profile != data_profile) { fprintf(stderr, "With mixed block groups data and metadata " @@ -1438,7 +1490,7 @@ raid_groups: if (!source_dir_set) { ret = create_raid_groups(trans, root, data_profile, data_profile_opt, metadata_profile, - metadata_profile_opt, mixed); + metadata_profile_opt, mixed, ssd); BUG_ON(ret); }