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I don't know what to do about high bo values is vmtstat. bi is 0 but bo is about 6000. So I don't know what that means and what to do. The application running on server is hanging. I don't know if it is because of that bo value. But if it is, what should I do?

Server is a 32 core AMD Opteron 2.4 GHz and has 256 GB of RAM.

The top command output is something like that:

Cpu(s):  0.5%us,  0.1%sy,  0.0%ni, 96.5%id,  2.9%wa,  0.0%hi,  0.0%si,  0.0%st
Mem:  264284404k total, 261750208k used,  2534196k free,  2923280k buffers
Swap: 266338296k total,    11624k used, 266326672k free, 247120176k cached
30009 db2inst1  25   0 6636m 754m 638m S 16.1  0.3   7938:49 db2sysc
11217 root      18   0 1324m 1.1g  49m S  1.0  0.4   5441:39 java
22270 db2fenc1  15   0 93976  14m 6828 S  1.0  0.0   5:29.50 db2fmp32
24419 root      15   0 13004 1376  820 R  1.0  0.0   0:00.49 top
22269 db2fenc1  15   0 93976  14m 6832 S  0.3  0.0   5:09.12 db2fmp32
    1 root      15   0 10348  700  584 S  0.0  0.0   0:12.16 init
    2 root      RT  -5     0    0    0 S  0.0  0.0   0:12.48 migration/0
    3 root      34  19     0    0    0 S  0.0  0.0   0:00.93 ksoftirqd/0
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1 Answer 1

up vote 2 down vote accepted

Some application is writing out data 6000 blocks per second. With a decent system that shouldn't be too much.

What that application is, we can't tell you since your post lacks a lot of information. You can see the per-application I/O statistics with the command iotop.

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I don't have iotop and iostat. Using redhat 5 without internet connection. Does it mean 6000 blocks per second is being written to disk? What information should I give? –  Ramazan POLAT Aug 17 '12 at 12:23
Yes, to disk. As a poor man's iotop you can use the ordinary top command and see if you see some processes constantly staying in D state. –  Janne Pikkarainen Aug 17 '12 at 12:25
When it comes to "What information I should provide?" Q .. Imagine YOU should answer to this question. I guess you would ask "What applications are running on your server?", "Are they supposed to be I/O intensive?", "Is it writing some actual data or is it just writing some log file like crazy?" and so on. –  Janne Pikkarainen Aug 17 '12 at 12:27
Ok. Everything is in S state. Supposing S column means State. And I have 4 disks configured as Raid 5. The application I am using is IBM content manager which saves files to disk and retrieves. I am so embarrassed, I should already know all of this. Thank you for you help. –  Ramazan POLAT Aug 17 '12 at 12:36
Yes, the S column is the state column. Many IBM software I've seen is like a Shakespeare or an ancient sea captain equivalent, they sure like to write lots of logs and other stuff. Keep your eye on /var/log or optionally the IBM software installation directory (perhaps under /opt somewhere) and see if log files grow fast. Then see if there's a way to tune the logging level down. –  Janne Pikkarainen Aug 17 '12 at 12:41

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