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Home -> Community -> Mailing Lists -> Oracle-L -> RE: Oracle on RAID - IOwait problem
How write-intensive is your application? Apps that do a lot of writing can
be terribly i/o bound on RAID 5 (I speak from bitter experience...). Reads
on the other hand are fine.
-----Original Message-----
From: Calvin Lim [mailto:calvin-lim_at_mediaring.com]
Sent: Friday, May 05, 2000 2:55 AM
To: Multiple recipients of list ORACLE-L
Subject: Oracle on RAID - IOwait problem
Hi,
We've just put a 8.1.5 on a 2CPU Sun Solaris into production.
The machine is hooked on to a RAID5 storage device by Seek. Oracle datafiles are spread across 3 channels on the RAID. What i'm noticing is that the disk iowait is reaching incredible levels and top is reporting 0.0% idle for CPU states and 100M swaps.
We're currently suspecting that it could be 1. the RAID configuration thats giving problem, 2. some cron driven perl/DBI jobs that is pounding the Database too often too hard with inefficient queries.
Could 2. be a reason for extensive iowaits thats always hovers round the 85% mark. I need some advise on how one would go about troubleshooting such iowait related problems? Thanks very much.
Regards,
Calvin
load averages: 0.39, 0.43, 0.46 22:19:3074 processes: 71 sleeping, 1 running, 2 on cpu CPU states: 0.0% idle, 5.2% user, 8.5% kernel, 86.3% iowait, 0.0% swap Memory: 1024M real, 16M free, 100M swap in use, 1900M swap free
PID USERNAME THR PRI NICE SIZE RES STATE TIME CPU COMMAND
2359 root 1 59 0 1944K 1080K sleep 0:03 2.40% sshd1 29216 oracle 1 58 0 832M 799M cpu0 1:50 2.12% oracle 2383 oracle 1 58 0 2000K 1360K cpu2 0:00 1.24% top 29214 mrurl 1 53 2 13M 4840K run 0:54 0.98% ifmxTrigger 10591 oracle 1 60 0 834M 798M sleep 102:23 0.95% oracle 27178 oracle 1 38 0 2000K 1160K sleep 0:55 0.51% top 10360 oracle 1 60 0 832M 798M sleep 113:10 0.50% oracle 10362 oracle 1 60 0 832M 797M sleep 112:00 0.49% oracle 10366 oracle 1 60 0 832M 797M sleep 111:50 0.42% oracle 10364 oracle 1 60 0 832M 798M sleep 112:27 0.41% oracle 10368 oracle 1 60 0 832M 797M sleep 112:16 0.38% oracle 2389 oracle 1 60 0 831M 799M sleep 0:00 0.19% oracle 10338 oracle 1 59 0 833M 794M sleep 3:01 0.15% oracle 10340 oracle 1 58 0 832M 794M sleep 4:40 0.14% oracle 9341 oracle 1 48 0 8960K 2352K sleep 9:34 0.13% tnslsnr ----------------
-- Author: Calvin Lim INET: calvin-lim_at_mediaring.com Fat City Network Services -- (858) 538-5051 FAX: (858) 538-5051 San Diego, California -- Public Internet access / Mailing Lists -------------------------------------------------------------------- To REMOVE yourself from this mailing list, send an E-Mail message to: ListGuru_at_fatcity.com (note EXACT spelling of 'ListGuru') and in the message BODY, include a line containing: UNSUB ORACLE-L (or the name of mailing list you want to be removed from). You may also send the HELP command for other information (like subscribing).Received on Fri May 05 2000 - 15:31:57 CDT