Disk speed differences under 2.6.0

From: Gordon Larsen (glarsen@alpha.homedns.org)
Date: Fri Aug 01 2003 - 08:54:26 EST


My apologies if this has already been discussed - but has anyone noticed
disk I/O speed differences under 2.6.0 as compared to 2.4.20? My system has
an ASUS A7V333 MB with 768M Ram, a 1300MHz Duron, three 40GB Maxtor drives
running linux software raid. See the screen capture below:

-----------------------------
2.4.20-19.9 -----------------------------------------------
[root@alpha root]# uname -a
Linux alpha 2.4.20-19.9 #1 Mon Jul 28 18:59:34 MDT 2003 i686 athlon i386
GNU/Linux
[root@alpha root]# hdparm -t /dev/md0

/dev/md0:
 Timing buffered disk reads: 64 MB in 2.90 seconds = 22.07 MB/sec
[root@alpha root]# hdparm -t /dev/md1

/dev/md1:
 Timing buffered disk reads: 64 MB in 1.66 seconds = 38.55 MB/sec
[root@alpha root]# hdparm -t /dev/md2

/dev/md2:
 Timing buffered disk reads: 64 MB in 0.96 seconds = 66.67 MB/sec
[root@alpha root]# hdparm -t /dev/md3

/dev/md3:
 Timing buffered disk reads: 64 MB in 1.74 seconds = 36.78 MB/sec
[root@alpha root]# hdparm -t /dev/md4

/dev/md4:
 Timing buffered disk reads: 64 MB in 1.74 seconds = 36.78 MB/sec
[root@alpha root]# hdparm -t /dev/md5

/dev/md5:
 Timing buffered disk reads: 64 MB in 1.68 seconds = 38.10 MB/sec
[root@alpha root]# hdparm -t /dev/md6

/dev/md6:
 Timing buffered disk reads: 64 MB in 1.70 seconds = 37.65 MB/sec

-----------------------------
2.6.0-0.test.2.1.28 -----------------------------------------------

[root@alpha root]# uname -a
Linux alpha 2.6.0-0.test2.1.28custom #1 Thu Jul 31 20:02:20 MDT 2003 i686
athlon i386 GNU/Linux
[root@alpha root]# hdparm -t /dev/md0

/dev/md0:
 Timing buffered disk reads: 64 MB in 2.67 seconds = 24.00 MB/sec
[root@alpha root]# hdparm -t /dev/md1

/dev/md1:
 Timing buffered disk reads: 64 MB in 1.92 seconds = 33.37 MB/sec
[root@alpha root]# hdparm -t /dev/md2

/dev/md2:
 Timing buffered disk reads: 64 MB in 1.37 seconds = 46.79 MB/sec
[root@alpha root]# hdparm -t /dev/md3

/dev/md3:
 Timing buffered disk reads: 64 MB in 2.23 seconds = 28.69 MB/sec
[root@alpha root]# hdparm -t /dev/md4

/dev/md4:
 Timing buffered disk reads: 64 MB in 2.20 seconds = 29.07 MB/sec
[root@alpha root]# hdparm -t /dev/md5

/dev/md5:
 Timing buffered disk reads: 64 MB in 2.03 seconds = 31.45 MB/sec
[root@alpha root]# hdparm -t /dev/md6

/dev/md6:
 Timing buffered disk reads: 64 MB in 1.99 seconds = 32.23 MB/sec

-----------------------------
Mounts -----------------------------------------------

[root@alpha root]# mount
/dev/md0 on / type ext3 (rw)
none on /proc type proc (rw)
usbdevfs on /proc/bus/usb type usbdevfs (rw)
/dev/md1 on /boot type ext3 (rw)
none on /dev/pts type devpts (rw,gid=5,mode=620)
/dev/md3 on /home type ext3 (rw)
none on /dev/shm type tmpfs (rw)
/dev/md6 on /tmp type ext3 (rw)
/dev/md4 on /usr type ext3 (rw)
/dev/md5 on /var type ext3 (rw)

----------------------------- MD Device
dump -----------------------------------------------

[root@alpha root]# lsraid -R -p
# md device [dev 9, 2] /dev/md2 queried online
raiddev /dev/md2
        raid-level 0
        nr-raid-disks 2
        nr-spare-disks 0
        persistent-superblock 1
        chunk-size 64

        device /dev/hde1
        raid-disk 0
        device /dev/hdg2
        raid-disk 1

# md device [dev 9, 1] /dev/md1 queried online
raiddev /dev/md1
        raid-level 1
        nr-raid-disks 2
        nr-spare-disks 0
        persistent-superblock 1
        chunk-size 64

        device /dev/hde2
        raid-disk 0
        device /dev/hdg1
        raid-disk 1

# md device [dev 9, 4] /dev/md4 queried online
raiddev /dev/md4
        raid-level 5
        nr-raid-disks 3
        nr-spare-disks 0
        persistent-superblock 1
        chunk-size 64

        device /dev/hde3
        raid-disk 0
        device /dev/hdg3
        raid-disk 1
        device /dev/hdh3
        raid-disk 2

# md device [dev 9, 3] /dev/md3 queried online
raiddev /dev/md3
        raid-level 5
        nr-raid-disks 3
        nr-spare-disks 0
        persistent-superblock 1
        chunk-size 64

        device /dev/hde5
        raid-disk 0
        device /dev/hdg5
        raid-disk 1
        device /dev/hdh5
        raid-disk 2

# md device [dev 9, 5] /dev/md5 queried online
raiddev /dev/md5
        raid-level 5
        nr-raid-disks 3
        nr-spare-disks 0
        persistent-superblock 1
        chunk-size 64

        device /dev/hde6
        raid-disk 0
        device /dev/hdg6
        raid-disk 1
        device /dev/hdh6
        raid-disk 2

# md device [dev 9, 0] /dev/md0 queried online
raiddev /dev/md0
        raid-level 1
        nr-raid-disks 2
        nr-spare-disks 0
        persistent-superblock 1
        chunk-size 64

        device /dev/hde7
        raid-disk 0
        device /dev/hdg7
        raid-disk 1

# md device [dev 9, 6] /dev/md6 queried online
raiddev /dev/md6
        raid-level 5
        nr-raid-disks 3
        nr-spare-disks 0
        persistent-superblock 1
        chunk-size 64

        device /dev/hde8
        raid-disk 0
        device /dev/hdg8
        raid-disk 1
        device /dev/hdh8
        raid-disk 2

[root@alpha root]#

--------------------------------
end-of-capture -----------------------------------------------

Cheers...Gord

-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/



This archive was generated by hypermail 2b29 : Thu Aug 07 2003 - 22:00:16 EST