Gentoo Archives: gentoo-user

From: Adam Carter <adamcarter3@×××××.com>
To: gentoo-user@l.g.o
Subject: [gentoo-user] Normal disk speed?
Date: Thu, 30 Sep 2010 11:06:49
Message-Id: AANLkTikO0WGfQjHMuCa_2Z0gdGa5Ovg97iQGU5FRekAK@mail.gmail.com
Taring my mp3 collection from 2.5in 500MB internal sata drive (sda) to esata
3.5in 500MB drive (sdb) and it seems slow. In vmstat i can see that the
external drive writes faster than the internal can read (external has
periods of inactivity)
# time tar cf /mnt/usbdrive/mp3back.tar mp3/

real    10m9.679s
user    0m1.577s
sys    2m1.769s
# du -ks mp3/
21221661    mp3/

So 21221MB in 610 seconds = 35 MB/s

# hdparm -t /dev/sda

/dev/sda:
 Timing buffered disk reads:  220 MB in  3.01 seconds =  73.14 MB/sec (77
with --direct)

FWIW;
# hdparm /dev/sda

/dev/sda:
 multcount     = 16 (on)
 IO_support    =  1 (32-bit)
 readonly      =  0 (off)
 readahead     = 256 (on)
 geometry      = 60801/255/63, sectors = 976773168, start = 0


So the should i expect filesystem (reiser3) and other overhead to cut the
read performance to less than half of what hdparm reports? Anything else i
can look at to speed it up? Im using CFQ io scheduler.

Replies

Subject Author
Re: [gentoo-user] Normal disk speed? Florian Philipp <lists@××××××××××××××××××.net>
[gentoo-user] Re: Normal disk speed? James <wireless@×××××××××××.com>
Re: [gentoo-user] Normal disk speed? Volker Armin Hemmann <volkerarmin@××××××××××.com>