Re: sudden drop in delete performance

surabhi.ahuja wrote:
> after my update
> I had my entire data drectory PGDATA removed,
> i had done initdb again
> and did lot of inserts (the inserts have given the similar performance)

So you _didn't_ vacuum analyze. You need one right at this point, or the
database is optimizing your queries using statistical data that is no
longer accurate (If I understand correctly, the statistics describe an
empty database - I need to read up on this topic sometime, I use it a
lot...).

> i then do a remove from the db, which is taking time.
> when i had postgres 8.0.0 i did not turn fsyn off.

> that time i had moved the pg_xlog directory to a diff partition and
> created a link from PGDATA to its new location.
> (i did this because i had heard tha it boosts performanne)

I'm rather certain creating a tablespace on that partition would be
faster than a symlink, although I suppose the filesystem cache will help
a bit.

> but I am doing the same here also (i mean with Postgres 8.1.5)

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Alban Hertroys
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