Different performance
Larry D Sorensen
larry.sorensen at juno.com
Fri May 9 22:58:19 UTC 2008
Please include information on the databases including versions. It could
just be different configurations on the databases. Are the patches up to
date and equal on both servers?
On Fri, 9 May 2008 14:11:25 -0700 Tina Tian <tinatianxia at hotmail.com>
writes:
I am a DBA. I have identical database servers running on two Linux redhat
4, host 1 and host 2. When I was running the same bulk load to database
(load a data file to database), host 2 was much faster than host 1.
On both host1 and host2, database are using file system mount on /dev/sda
and /dev/sdb.
I checked with my SA, host1 and host2 have same CPU, RAM, file system
configuration. The only different is that host 2 has extra HD capacity
with higher 15k RPM. But the extra 2 HDs(sdc and sdd) are dedicated to
other applications, not used by database at all.
My questions are:
-----------------
1. On host2 (faster), the extra faster HDs(/dev/sdc and sdd) are not used
by database. Does it still affect IO performance of /dev/sda and /dev/sdb
?
2. During database bulk load testing, host 1(slower) shows longer service
IO time (svctm) and longer IO waiting time(await).
What other possible reason can cause this problem? Any idea?
I did post the same issue to database discussion group and they suggested
me to check OS performance(svctm).
Below is the result from iostat on host1(slower) and host2(faster) during
bulk load:
Host 1: iostat -x 2
=====================
avg-cpu: %user %nice %sys %iowait %idle
0.15 0.00 0.07 0.28 99.49
Device: rrqm/s wrqm/s r/s w/s rsec/s wsec/s rkB/s wkB/s
avgrq-sz avgqu-sz await svctm %util
sda 0.01 0.59 0.24 0.19 29.22 6.17 14.61 3.08
83.49 0.01 21.71 3.84 0.16
sdb 0.04 10.05 0.89 3.74 117.37 110.34 58.69 55.17
49.13 0.10 21.76 4.48 2.08
avg-cpu: %user %nice %sys %iowait %idle
15.74 0.00 8.99 0.31 74.95
Device: rrqm/s wrqm/s r/s w/s rsec/s wsec/s rkB/s wkB/s
avgrq-sz avgqu-sz await svctm %util
sda 1.99 0.00 57.71 0.00 14025.87 0.00 7012.94 0.00
243.03 0.21 3.58 3.53 20.35
sdb 0.00 0.00 11.94 0.00 95.52 0.00 47.76 0.00
8.00 0.02 2.04 2.04 2.44
avg-cpu: %user %nice %sys %iowait %idle
6.18 0.00 2.37 9.24 82.20
Device: rrqm/s wrqm/s r/s w/s rsec/s wsec/s rkB/s wkB/s
avgrq-sz avgqu-sz await svctm %util
sda 0.50 0.50 23.00 1.00 5732.00 12.00 2866.00 6.00
239.33 0.07 3.08 3.02 7.25
sdb 0.00 129.00 7.00 130.00 56.00 2076.00 28.00 1038.00
15.56 0.75 5.49 5.40 73.95
avg-cpu: %user %nice %sys %iowait %idle
0.06 0.00 0.12 12.44 87.38
Device: rrqm/s wrqm/s r/s w/s rsec/s wsec/s rkB/s wkB/s
avgrq-sz avgqu-sz await svctm %util
sda 0.00 3.50 0.00 3.00 0.00 52.00 0.00 26.00
17.33 0.03 10.00 3.67 1.10
sdb 0.00 182.50 0.00 182.50 0.00 2920.00 0.00 1460.00
16.00 0.99 5.44 5.44 99.30
avg-cpu: %user %nice %sys %iowait %idle
0.00 0.00 0.12 12.49 87.38
Device: rrqm/s wrqm/s r/s w/s rsec/s wsec/s rkB/s wkB/s
avgrq-sz avgqu-sz await svctm %util
sda 0.00 0.50 0.00 1.01 0.00 12.06 0.00 6.03
12.00 0.01 6.00 6.00 0.60
sdb 0.00 184.92 0.00 185.43 0.00 2962.81 0.00 1481.41
15.98 1.01 5.45 5.38 99.70
avg-cpu: %user %nice %sys %iowait %idle
0.00 0.00 0.06 12.43 87.51
Device: rrqm/s wrqm/s r/s w/s rsec/s wsec/s rkB/s wkB/s
avgrq-sz avgqu-sz await svctm %util
sda 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00
0.00 0.00 0.00 0.00 0.00
sdb 0.00 184.08 0.00 184.08 0.00 2945.27 0.00 1472.64
16.00 0.99 5.39 5.38 99.00
avg-cpu: %user %nice %sys %iowait %idle
0.00 0.00 0.12 12.31 87.56
Device: rrqm/s wrqm/s r/s w/s rsec/s wsec/s rkB/s wkB/s
avgrq-sz avgqu-sz await svctm %util
sda 0.00 1.00 0.00 1.50 0.00 20.00 0.00 10.00
13.33 0.02 15.33 6.67 1.00
sdb 0.00 181.00 0.00 181.00 0.00 2896.00 0.00 1448.00
16.00 0.99 5.48 5.49 99.40
avg-cpu: %user %nice %sys %iowait %idle
0.00 0.00 0.19 12.37 87.45
Device: rrqm/s wrqm/s r/s w/s rsec/s wsec/s rkB/s wkB/s
avgrq-sz avgqu-sz await svctm %util
sda 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00
0.00 0.00 0.00 0.00 0.00
sdb 0.00 178.00 0.00 178.50 0.00 2852.00 0.00 1426.00
15.98 1.00 5.61 5.55 99.10
avg-cpu: %user %nice %sys %iowait %idle
0.00 0.00 0.12 12.37 87.51
Device: rrqm/s wrqm/s r/s w/s rsec/s wsec/s rkB/s wkB/s
avgrq-sz avgqu-sz await svctm %util
sda 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00
0.00 0.00 0.00 0.00 0.00
sdb 0.00 179.50 0.00 179.50 0.00 2872.00 0.00 1436.00
16.00 0.99 5.52 5.53 99.25
avg-cpu: %user %nice %sys %iowait %idle
0.00 0.00 0.06 12.44 87.50
Device: rrqm/s wrqm/s r/s w/s rsec/s wsec/s rkB/s wkB/s
avgrq-sz avgqu-sz await svctm %util
sda 0.00 1.50 0.00 3.50 0.00 40.00 0.00 20.00
11.43 0.07 20.00 4.00 1.40
sdb 0.00 179.00 0.00 179.50 0.00 2868.00 0.00 1434.00
15.98 1.02 5.68 5.53 99.30
avg-cpu: %user %nice %sys %iowait %idle
0.06 0.00 0.19 12.41 87.34
Device: rrqm/s wrqm/s r/s w/s rsec/s wsec/s rkB/s wkB/s
avgrq-sz avgqu-sz await svctm %util
sda 0.00 0.50 0.00 1.00 0.00 12.00 0.00 6.00
12.00 0.01 6.50 6.50 0.65
sdb 0.00 183.50 0.00 183.50 0.00 2936.00 0.00 1468.00
16.00 0.99 5.40 5.41 99.25
Host 2: iostat -x 2
==================
avg-cpu: %user %nice %sys %iowait %idle
0.96 0.00 0.69 0.21 98.15
Device: rrqm/s wrqm/s r/s w/s rsec/s wsec/s rkB/s wkB/s
avgrq-sz avgqu-sz await svctm %util
hda 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00
48.00 0.00 1.33 1.33 0.00
sda 0.01 5.31 0.23 1.55 17.96 54.93 8.98 27.47
40.76 0.07 41.59 1.21 0.22
sdb 0.03 3.99 0.84 0.47 113.52 35.67 56.76 17.83
114.36 0.03 23.00 2.55 0.33
sdc 0.05 37.80 0.58 1.50 131.96 314.37 65.98 157.19
214.93 0.43 205.85 2.84 0.59
sdd 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00
40.35 0.00 3.52 3.52 0.00
avg-cpu: %user %nice %sys %iowait %idle
16.03 0.00 8.61 0.44 74.92
Device: rrqm/s wrqm/s r/s w/s rsec/s wsec/s rkB/s wkB/s
avgrq-sz avgqu-sz await svctm %util
hda 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00
0.00 0.00 0.00 0.00 0.00
sda 1.99 14.43 57.71 6.97 13775.12 171.14 6887.56 85.57
215.63 0.22 3.43 3.36 21.74
sdb 0.00 357.71 7.96 358.71 63.68 5731.34 31.84 2865.67
15.80 0.04 0.10 0.10 3.83
sdc 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00
0.00 0.00 0.00 0.00 0.00
sdd 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00
0.00 0.00 0.00 0.00 0.00
avg-cpu: %user %nice %sys %iowait %idle
15.62 0.00 8.81 0.56 75.00
Device: rrqm/s wrqm/s r/s w/s rsec/s wsec/s rkB/s wkB/s
avgrq-sz avgqu-sz await svctm %util
hda 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00
0.00 0.00 0.00 0.00 0.00
sda 1.50 0.00 56.00 0.00 13964.00 0.00 6982.00 0.00
249.36 0.22 3.90 3.89 21.80
sdb 0.00 635.00 7.00 635.00 64.00 10160.00 32.00 5080.00
15.93 0.06 0.09 0.09 5.55
sdc 0.00 1.00 0.00 1.50 0.00 20.00 0.00 10.00
13.33 0.00 0.00 0.00 0.00
sdd 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00
0.00 0.00 0.00 0.00 0.00
Thanks,
Tina
Sign in and you could WIN! Enter for your chance to win $1000 every day.
Visit SignInAndWIN.ca today to learn more!
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://listman.redhat.com/archives/redhat-sysadmin-list/attachments/20080509/9dc09db5/attachment.htm>
More information about the redhat-sysadmin-list
mailing list