Thread: simulating high load for vacuum full

simulating high load for vacuum full

From
Ivan Sergio Borgonovo
Date:
I'm trying to diagnose a problem that happened during vacuum full.

It is a programming problem triggered by some lock, delay whatever,
happening during vacuum.

Making large updates to a bunch of tables is a PITA just to obtain a
slow VACUUM FULL.

Restoring a "fragmented" DB doesn't look as a working strategy.
The restore shouldn't be fragmented.

What are the "side effects" of a vacuum full?
Any cheaper way to cause a heavy vacuum full or just its side
effects?

thanks

--
Ivan Sergio Borgonovo
http://www.webthatworks.it


Re: simulating high load for vacuum full

From
Bill Moran
Date:
In response to Ivan Sergio Borgonovo <mail@webthatworks.it>:

> I'm trying to diagnose a problem that happened during vacuum full.

What _is_ the problem?

> It is a programming problem triggered by some lock, delay whatever,
> happening during vacuum.

The solution is to fix the lock, delay, or whatever issue.

> Making large updates to a bunch of tables is a PITA just to obtain a
> slow VACUUM FULL.

I don't understand what that sentence is supposed to mean.

> Restoring a "fragmented" DB doesn't look as a working strategy.
> The restore shouldn't be fragmented.

It won't be.

> What are the "side effects" of a vacuum full?

Index fragmentation.  Table locks that block other processes until the
vacuum full is complete.  Heavy disk activity.

> Any cheaper way to cause a heavy vacuum full or just its side
> effects?

Huh?  Are you try to simulate a vacuum full for testing, or are you
complaining about the side effects of vacuum full?

Quite honestly, I can't figure out what your question is or what you're
trying to do.

--
Bill Moran
http://www.potentialtech.com
http://people.collaborativefusion.com/~wmoran/