Original Posting:
> We do oracle exports during the night and have had errors and I am looking
>real hard at the defragment job. Does anyone have any words of wisdom on
>the defragment job that runs by default in roots cron? The default period
>is from 0100 to 0500. Can I make it run faster by using the -T option or
-t
>option, or does that just stop it before the defrag is complete? The man
>page is not real clear on that. Does anyone not use it and why? Has anyone
>seen problems with it during oracle exports? Has anyone modified the
>defaults? Any help is appreciated and I will summarize.
Summary:
Many thanks to all who replied. Responses varied from "I run it only when
no other activity is present" to "If you value your data don't run
defragment" Oy. Bottom line is I commented out the cron job and replaced
it with one that uses the -vn argument and mails me the results. This will
merely look at the ADVFS stats and let you know when your fs is getting
fragged. Then I will schedule a time to stop all system activity (I'm
allotted 2 seconds a month) and backup and defrag. The pertinent data is
Aggregate I/O perf and Avg exts per file w/exts. The best case is 100% for
the first and 1.00 for the last. Special thanks to Bryan Lavelle and Tom
Blinn who took the time to respond to a couple of additional questions and
clarification of the ADVFS. Here is a sample of my defrag after 2 days of
not defragging:
> defragment -vn domain02
defragment: Gathering data for domain 'domain02'
Current domain data:
Extents: 7075
Files w/extents: 6851
Avg exts per file w/exts: 1.03
Aggregate I/O perf: 100%
Free space fragments: 146
<100K <1M <10M >10M
Free space: 0% 0% 1% 98%
Fragments: 41 70 15 20
By the way my exports and backups now take half the time. The defrag
process must be a real hog of resources.
Roger D. Leonard
Roger D. Leonard
Unix Systems Engineer
HealthAmerica, Pgh PA
rleonard_at_cvty.com
Received on Mon Jun 07 1999 - 13:53:54 NZST