Re: full vacuum really slows down query

Yes. 
This is what I do.
1. Vacuum full
2. Reindex force
This is done ever night

My users complained about a report being slow.

I grabbed a dump and restored it to my development machine.

The query worked just fine, but not on the production server.

I did a vacuum full and then reran the query.  Now it performs just as
slow as on the production machine.  That is the only change I made.

I am in the process of trying to figure out the EXPLAIN ANALYZE for
both queries, but I have never had to read this output and I am
unfamiliar with how to find the problem.  I will post both here and
maybe someone can help me out.



Joshua D. Drake wrote:


On Wed, 2008-06-04 at 17:02 -0500, Jason Long wrote:


    I have a query that takes 2 sec if I run it from a freshly restored
dump.  If I run a full vacuum on the database it then takes 30 seconds.



If you run it a second time after the vacuum full?

Joshua D. Drake