Re: Ten percent test

Gene Heskett
2007-04-08T17:57:17Z

On Sunday 08 April 2007, Mike Galbraith wrote:
>On Sun, 2007-04-08 at 07:33 -0400, Gene Heskett wrote:
>> That seems to be the killer loading here, building a kernel (make -j3)
>> doesn't seem to lag it all that bad. One session of gzip -best makes
>> it fall plumb over though, which was a disappointment.
>
>Can you make a testcase that doesn't require amanda?
>
> -Mike

Sure. Try 'tar czf nameofarchive.tar.gz /path/to-dir-to-be-backed-up'

Or, from the runtar log from this morning, and this is all one line:

runtar.20070408022016.debug:running: /bin/tar: 'gtar' '--create' '--file' '-' '--directory' '/usr/dlds-rpms' '--one-file-system' '--listed-incremental' '/usr/local/var/amanda/gnutar-lists/coyote_usr_dlds-rpms_1.new' '--sparse' '--ignore-failed-read' '--totals' '--exclude-from' '/tmp/amanda/sendbackup._usr_dlds-rpms.20070408022016.exclude' '.'

and amanda will if requested, pipe that output through a |gzip -best, and
its this process that brings the machine to the table begging for scraps
like a puppy. Tar by itself can be felt but isn't bad.

Even without the -best switch in effect, I'm sure you'll see the machine
slow considerably.

Please don't try to call amanda an unusual load as amanda itself is
nothing but an intelligent manager, constructing the command lines passed
to tar or dump, and gzip, which do the real work. Amdump, the manager my
scripts wrap around, and my scripts themselves, will not use more
than .01% of the cpu when averaged over the whole backup session.

--
Cheers, Gene
"There are four boxes to be used in defense of liberty:
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-Ed Howdershelt (Author)
We are Microsoft. What you are experiencing is not a problem; it is an
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