From: Marc MERLIN <marc@merlins.org>
To: "Fajar A. Nugraha" <list@fajar.net>
Cc: "linux-btrfs@vger.kernel.org" <linux-btrfs@vger.kernel.org>
Subject: Re: How can btrfs take 23sec to stat 23K files from an SSD?
Date: Tue, 31 Jul 2012 23:21:56 -0700 [thread overview]
Message-ID: <20120801062156.GI12695@merlins.org> (raw)
In-Reply-To: <CAG1y0sdnyv4O8zab+WwLxZ6qUJTcVryrAgnDfv5eiAw+eZh-Gg@mail.gmail.com>
On Wed, Aug 01, 2012 at 01:08:46PM +0700, Fajar A. Nugraha wrote:
> > It it were a random crappy SSD from a random vendor, I'd blame the SSD, but
> > I have a hard time believing that samsung is selling SSDs that are slower
> > than hard drives at random IO and 'seeks'.
>
> You'd be surprised on how badly some vendors can screw up :)
At some point, it may come down to that indeed :-/
I'm still hopefully that Samsung didn't, but we'll see.
> > First: btrfs is the slowest:
>
> > gandalfthegreat:/mnt/ssd/var/local# grep /mnt/ssd/var /proc/mounts
> > /dev/mapper/ssd /mnt/ssd/var btrfs rw,noatime,compress=lzo,ssd,discard,space_cache 0 0
>
> Just checking, did you explicitly activate "discard"? Cause on my
Yes. Note that it should a noop when all you're doing is stating inodes and
not writing (I'm using noatime).
> setup (with corsair SSD) it made things MUCH slower. Also, try adding
> "noatime" (just in case the slow down was because "du" cause many
> access time updates)
I have noatime in there already :)
Marc
--
"A mouse is a device used to point at the xterm you want to type in" - A.S.R.
Microsoft is to operating systems ....
.... what McDonalds is to gourmet cooking
Home page: http://marc.merlins.org/
next prev parent reply other threads:[~2012-08-01 6:21 UTC|newest]
Thread overview: 69+ messages / expand[flat|nested] mbox.gz Atom feed top
2012-07-25 15:45 du -s src is a lot slower on SSD than spinning disk in the same laptop Marc MERLIN
[not found] ` <alpine.LFD.2.00.1207252023080.4340@(none)>
2012-07-25 23:38 ` Marc MERLIN
2012-07-26 3:32 ` Ted Ts'o
2012-07-26 3:35 ` Marc MERLIN
2012-07-26 6:54 ` Marc MERLIN
2012-08-01 5:30 ` Marc MERLIN
2012-08-01 6:01 ` How can btrfs take 23sec to stat 23K files from an SSD? Marc MERLIN
2012-08-01 6:08 ` Fajar A. Nugraha
2012-08-01 6:21 ` Marc MERLIN [this message]
2012-08-01 21:57 ` Martin Steigerwald
2012-08-02 5:07 ` Marc MERLIN
2012-08-02 11:18 ` Martin Steigerwald
2012-08-02 17:39 ` Marc MERLIN
2012-08-02 20:20 ` Martin Steigerwald
2012-08-02 20:44 ` Marc MERLIN
2012-08-02 21:21 ` Martin Steigerwald
2012-08-02 21:49 ` Marc MERLIN
2012-08-03 18:45 ` Martin Steigerwald
2012-08-16 7:45 ` Marc MERLIN
2012-08-02 11:25 ` Martin Steigerwald
2012-08-01 6:36 ` Chris Samuel
2012-08-01 6:40 ` Marc MERLIN
2012-08-01 8:18 ` du -s src is a lot slower on SSD than spinning disk in the same laptop Spelic
2012-08-16 7:50 ` Marc MERLIN
[not found] ` <502CC2A2.4010506@shiftmail.org>
2012-08-16 17:55 ` Marc MERLIN
2012-09-05 16:52 ` ext4 crash with 3.5.2 in ext4_ext_remove_space Marc MERLIN
2012-09-05 17:50 ` Lukáš Czerner
2012-09-05 17:53 ` Marc MERLIN
2012-09-06 4:24 ` Marc MERLIN
2012-09-07 15:19 ` Marc MERLIN
2012-09-07 15:39 ` Lukáš Czerner
2012-09-07 15:51 ` Marc MERLIN
-- strict thread matches above, loose matches on Subject: below --
2012-07-24 6:18 How can btrfs take 23sec to stat 23K files from an SSD? Marc MERLIN
2012-01-30 0:37 brtfs on top of dmcrypt with SSD. No corruption iff write cache off? Marc MERLIN
2012-02-01 17:56 ` Chris Mason
2012-02-02 3:23 ` Marc MERLIN
2012-02-02 12:42 ` Chris Mason
[not found] ` <20120202152722.GI12429@merlins.org>
2012-02-12 22:32 ` Marc MERLIN
2012-02-12 23:47 ` Milan Broz
2012-02-13 0:14 ` Marc MERLIN
2012-02-15 15:42 ` Calvin Walton
2012-02-15 16:55 ` Marc MERLIN
2012-02-15 16:59 ` Hugo Mills
2012-02-22 10:28 ` Justin Ossevoort
2012-02-22 11:07 ` Hugo Mills
2012-02-16 6:33 ` Chris Samuel
2012-02-18 12:33 ` Martin Steigerwald
2012-02-18 12:39 ` Martin Steigerwald
2012-02-18 12:49 ` Martin Steigerwald
2012-07-18 18:13 ` brtfs on top of dmcrypt with SSD -> Trim or no Trim Marc MERLIN
2012-07-18 20:04 ` Fajar A. Nugraha
2012-07-18 20:37 ` Marc MERLIN
2012-07-18 21:34 ` Clemens Eisserer
2012-07-18 21:48 ` Marc MERLIN
2012-07-18 21:49 ` Martin Steigerwald
2012-07-18 22:04 ` Marc MERLIN
2012-07-19 10:40 ` Martin Steigerwald
2012-07-22 18:58 ` brtfs on top of dmcrypt with SSD -> ssd or nossd + crypt performance? Marc MERLIN
2012-07-22 19:35 ` Martin Steigerwald
2012-07-22 19:43 ` Martin Steigerwald
2012-07-22 20:44 ` Marc MERLIN
2012-07-22 22:41 ` brtfs on top of dmcrypt with SSD -> file access 5x slower than spinning disk Marc MERLIN
2012-07-23 6:42 ` How can btrfs take 23sec to stat 23K files from an SSD? Marc MERLIN
2012-07-24 7:56 ` Martin Steigerwald
2012-07-27 4:40 ` Marc MERLIN
2012-07-27 11:08 ` Chris Mason
2012-07-27 18:42 ` Marc MERLIN
2012-02-18 16:07 ` brtfs on top of dmcrypt with SSD. No corruption iff write cache off? Marc MERLIN
2012-02-19 0:53 ` Clemens Eisserer
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