From: "J.A. Magallón" <jamagallon@ono.com>
To: LKML <linux-kernel@vger.kernel.org>
Subject: Speed of SDHCI subsystem
Date: Tue, 19 May 2009 00:37:50 +0200 [thread overview]
Message-ID: <20090519003750.461abe7d@werewolf.home> (raw)
Hi all...
I have notice something strange with SD cards.
I have an Aspire One and had an 8Gb SDHC card that used for my home,
and have recently upgraded to a 16Gb one.
This new one came with an USB reader.
The thing is that cards look much faster when accessed through the USB
key that directly on the readers of the One.
Some numbers with hdparm:
TakeMS 8Gb Class 6:
Gives 10MB/s on the slot, 17MB/s via the USB key
SanDisk UltraII 16Gb, Class 4, advertised as 15Mb/s:
Gives 10MB/s on the slot, 14MB/s on USB
I know that hdparm is not a benchmark, but I supposed it should be
limited by the media, not the connection.
But somehow the SDHCI/MMC subsystem seems to be stuck at 10MB/s, independent
of the quality of the media.
Any ideas ?
--
J.A. Magallon <jamagallon()ono!com> \ Software is like sex:
\ It's better when it's free
Mandriva Linux release 2010.0 (Cooker) for x86_64
Linux 2.6.29.2-desktop-1mnb (gcc 4.3.2 (GCC) #1 Wed May
next reply other threads:[~2009-05-18 22:43 UTC|newest]
Thread overview: 4+ messages / expand[flat|nested] mbox.gz Atom feed top
2009-05-18 22:37 J.A. Magallón [this message]
2009-06-03 6:33 ` Speed of SDHCI subsystem Pierre Ossman
2009-06-17 21:45 ` J.A. Magallón
2009-06-22 14:11 ` Pierre Ossman
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=20090519003750.461abe7d@werewolf.home \
--to=jamagallon@ono.com \
--cc=linux-kernel@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