Frederic posted an interesting link to the seeker io script in the sysbench fileio vs small EC2 article.

He was concerned that the seeker was showing difference numbers to sysbench fileio, especially on the /mnt mountpoint.

I read the thread and there was another comment made concerning how Xen could use a sparse file image to improve the io performance. I tested that theory out and found as soon as I created a reasonable sized file on /mnt, the performance dropped significantly to less than 20% of the empty mountpoint performance.

I appreciate the feedback I receive via comments. Most of the feedback I have derive purely from Google web analytics and sitemap tools.

Results:

[root@domU-12-31-35-00-04-61 ~]# sudo hdparm -t /dev/sda1

/dev/sda1:
Timing buffered disk reads:  216 MB in  3.01 seconds =  71.68 MB/sec
[root@domU-12-31-35-00-04-61 ~]# sudo hdparm -t /dev/sda2

/dev/sda2:
Timing buffered disk reads:  380 MB in  3.00 seconds = 126.51 MB/sec


[root@domU-12-31-35-00-04-61 ~]# ./seeker /dev/sda1
Seeker v2.0, 2007-01-15, http://www.linuxinsight.com/how_fast_is_your_disk.html
Benchmarking /dev/sda1 [1025MB], wait 30 seconds..............................
Results: 278 seeks/second, 3.60 ms random access time

./seeker /dev/sda2

Seeker v2.0, 2007-01-15, http://www.linuxinsight.com/how_fast_is_your_disk.html
Benchmarking /dev/sda2 [152688MB], wait 30 seconds..............................
Results: 5741 seeks/second, 0.17 ms random access time

 Add a file to /mnt to test the sparse Xen image idea 

dd if=/dev/zero of=/mnt/zerofile bs=1024M

[root@domU-12-31-35-00-04-61 mnt]# ls -l
total 7347232
drwx------  2 root root      16384 Mar 16 12:38 lost+found
-rw-r--r--  1 root root        710 Mar 16 23:37 randomfile
-rw-r--r--  1 root root 7516192768 Mar 16 23:44 zerofile
[root@domU-12-31-35-00-04-61 mnt]# cd
[root@domU-12-31-35-00-04-61 ~]# df -k
Filesystem           1K-blocks      Used Available Use% Mounted on
/dev/sda1              1032056    885984     93592  91% /
/dev/sda2            153899044   7539888 138541532   6% /mnt
[root@domU-12-31-35-00-04-61 ~]# ./seeker /dev/sda2
Seeker v2.0, 2007-01-15, http://www.linuxinsight.com/how_fast_is_your_disk.html
Benchmarking /dev/sda2 [152688MB], wait 30 seconds.............................
Results: 1101 seeks/second, 0.91 ms random access time
[root@domU-12-31-35-00-04-61 ~]# ./seeker /dev/sda2
Seeker v2.0, 2007-01-15, http://www.linuxinsight.com/how_fast_is_your_disk.html
Benchmarking /dev/sda2 [152688MB], wait 30 seconds......................
Results: 582 seeks/second, 1.72 ms random access time
[root@domU-12-31-35-00-04-61 ~]# ./seeker /dev/sda2
Seeker v2.0, 2007-01-15, http://www.linuxinsight.com/how_fast_is_your_disk.html
Benchmarking /dev/sda2 [152688MB], wait 30 seconds.....................
Results: 177 seeks/second, 5.62 ms random access time
[root@domU-12-31-35-00-04-61 ~]# ./seeker /dev/sda2
Seeker v2.0, 2007-01-15, http://www.linuxinsight.com/how_fast_is_your_disk.html
Benchmarking /dev/sda2 [152688MB], wait 30 seconds.........................
Results: 881 seeks/second, 1.13 ms random access time
[root@domU-12-31-35-00-04-61 ~]# w
23:50:30 up  4:07,  1 user,  load average: 0.62, 3.77, 3.39
USER     TTY      FROM              LOGIN@   IDLE   JCPU   PCPU WHAT
root     ttyp0    203-19-70-133.pe 19:47    0.00s  0.01s  0.00s w
[root@domU-12-31-35-00-04-61 ~]# ./seeker /dev/sda2
Seeker v2.0, 2007-01-15, http://www.linuxinsight.com/how_fast_is_your_disk.html
Benchmarking /dev/sda2 [152688MB], wait 30 seconds....................
Results: 355 seeks/second, 2.82 ms random access time