homepage Welcome to WebmasterWorld Guest from 50.17.86.12
register, free tools, login, search, pro membership, help, library, announcements, recent posts, open posts,
Become a Pro Member
Home / Forums Index / Hardware and OS Related Technologies / Linux, Unix, and *nix like Operating Systems
Forum Library, Charter, Moderators: bakedjake

Linux, Unix, and *nix like Operating Systems Forum

    
Disk I/O Monitoring for Cent 5.6
Disk I/O Monitoring for Cent 5.6
Das Capitolin

5+ Year Member



 
Msg#: 4352328 posted 5:10 am on Aug 17, 2011 (gmt 0)

For the past month my Cent 5.6 server has suffered random I/O spikes that last from several minutes to many hours. I'm struggling to find the ideal tool to help track down the culprit, and hope the users here can offer some suggestions.

I've got Webmin installed which tells me basic I/O usage in %, but stops short of pointing out process I/O usage. I've also installed Cacti, but it doesn't appear I can run down the problem with it either. Using the vmstat command (vmstat 1 10) tells me almost nothing useful.

Please offer some guidance.

 

phranque

WebmasterWorld Administrator phranque us a WebmasterWorld Top Contributor of All Time 10+ Year Member Top Contributors Of The Month



 
Msg#: 4352328 posted 6:41 am on Aug 17, 2011 (gmt 0)

perhaps iostat will provide the information you need.

Das Capitolin

5+ Year Member



 
Msg#: 4352328 posted 2:34 pm on Aug 17, 2011 (gmt 0)

Thank you, but iostat (iostat -d -k -x) only shows me read/write activity on the disk. What I need is to see that information at a process level.

Das Capitolin

5+ Year Member



 
Msg#: 4352328 posted 2:38 pm on Aug 17, 2011 (gmt 0)

sar -b produces roughly the same results, so it won't work either.

bakedjake

WebmasterWorld Administrator bakedjake us a WebmasterWorld Top Contributor of All Time 10+ Year Member



 
Msg#: 4352328 posted 2:40 pm on Aug 17, 2011 (gmt 0)

block_dump is what you're looking for.

Be careful; only use it sparingly for short amounts of time as it generates massive (additional) disk activity.

Enable it with sysctl, then use /var/log/debug to find the culprit. Remember to disable it when you're done!

Das Capitolin

5+ Year Member



 
Msg#: 4352328 posted 2:52 pm on Aug 17, 2011 (gmt 0)

This one looks like a winner, thank you!

Global Options:
 top home search open messages active posts  
 

Home / Forums Index / Hardware and OS Related Technologies / Linux, Unix, and *nix like Operating Systems
rss feed

All trademarks and copyrights held by respective owners. Member comments are owned by the poster.
Home ¦ Free Tools ¦ Terms of Service ¦ Privacy Policy ¦ Report Problem ¦ About ¦ Library ¦ Newsletter
WebmasterWorld is a Developer Shed Community owned by Jim Boykin.
© Webmaster World 1996-2014 all rights reserved