From: Thomas Jarosch <thomas.jarosch@intra2net.com>
To: Andrei Banu <andrei.banu@redhost.ro>
Cc: linux-raid@vger.kernel.org
Subject: Re: Incredibly poor performance of mdraid-1 with 2 SSD Samsung 840 PRO
Date: Thu, 25 Apr 2013 13:38:17 +0200 [thread overview]
Message-ID: <15025553.voJ1cqAbWd@storm> (raw)
In-Reply-To: <51732422.1050109@redhost.ro>
On Sunday, 21. April 2013 02:26:26 Andrei Banu wrote:
> They are connected through SATA2 ports (this does explain the read speed
> but not the pitiful write one) in AHCI.
So the SATA controller is already in AHCI mode. Good.
You didn't say what kind of server hardware you are using or I missed it.
On the HP DL3xxx servers we usually use, we have to enable AHCI mode _and_
the write cache in the BIOS. Maybe your server needs something similar.
Some RAID controllers only allow you to enable the write cache
when a battery-backed write cache module is installed.
HTH,
Thomas
next prev parent reply other threads:[~2013-04-25 11:38 UTC|newest]
Thread overview: 38+ messages / expand[flat|nested] mbox.gz Atom feed top
2013-04-19 22:58 Incredibly poor performance of mdraid-1 with 2 SSD Samsung 840 PRO Andrei Banu
[not found] ` <CAH3kUhEaZGON=fAyVMZOz5fH_DcfKv=hCa96UCeK4pN7k81c_Q@mail.gmail.com>
[not found] ` <51725458.7020109@redhost.ro>
[not found] ` <CAH3kUhHxBiqugFQm=PPJNNe9jOdKy0etUjQNsoDz_LJNUCLCCQ@mail.gmail.com>
2013-04-20 23:25 ` Andrei Banu
2013-04-20 23:26 ` Andrei Banu
2013-04-21 2:48 ` Stan Hoeppner
2013-04-21 12:23 ` Tommy Apel
2013-04-21 16:48 ` Tommy Apel
2013-04-21 19:33 ` Stan Hoeppner
2013-04-21 19:56 ` Tommy Apel
2013-04-22 0:47 ` Stan Hoeppner
2013-04-22 7:51 ` Tommy Apel
2013-04-22 8:29 ` Tommy Apel
2013-04-22 10:26 ` Andrei Banu
2013-04-22 12:02 ` Tommy Apel
2013-04-23 2:59 ` Stan Hoeppner
2013-04-22 23:21 ` Stan Hoeppner
2013-04-25 11:38 ` Thomas Jarosch [this message]
2013-04-20 23:26 ` Andrei Banu
2013-04-21 0:10 ` Stan Hoeppner
[not found] ` <51732E2B.6090607@hardwarefreak.com>
2013-04-21 20:46 ` Andrei Banu
2013-04-21 23:17 ` Stan Hoeppner
2013-04-22 10:19 ` Andrei Banu
2013-04-23 2:51 ` Stan Hoeppner
2013-04-23 10:17 ` Andrei Banu
2013-04-24 3:24 ` Stan Hoeppner
2013-04-24 8:26 ` Andrei Banu
2013-04-24 9:12 ` Adam Goryachev
2013-04-24 10:24 ` Tommy Apel
2013-04-24 21:42 ` Andrei Banu
2013-04-24 21:40 ` Andrei Banu
2013-04-24 16:37 ` Stan Hoeppner
2013-04-24 21:46 ` Andrei Banu
[not found] ` <CAH3kUhHnF0imY=CAHfzaQy4XJuOMgOtbHNp17EYzeSJR2en7Fg@mail.gmail.com>
2013-04-25 10:11 ` Andrei Banu
2013-04-25 10:56 ` Stan Hoeppner
2013-04-22 23:11 ` Andrei Banu
2013-04-23 4:39 ` Stan Hoeppner
2013-04-22 23:25 ` Stan Hoeppner
2013-04-23 4:49 ` Mikael Abrahamsson
2013-04-23 6:01 ` Stan Hoeppner
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=15025553.voJ1cqAbWd@storm \
--to=thomas.jarosch@intra2net.com \
--cc=andrei.banu@redhost.ro \
--cc=linux-raid@vger.kernel.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox