Re: is pg_autovacuum so effective ? - Mailing list pgsql-performance

From Gaetano Mendola
Subject Re: is pg_autovacuum so effective ?
Date
Msg-id 421BD64E.30803@bigfoot.com
Whole thread Raw
In response to Re: is pg_autovacuum so effective ?  (Tom Lane <tgl@sss.pgh.pa.us>)
List pgsql-performance
Tom Lane wrote:
> Gaetano Mendola <mendola@bigfoot.com> writes:
>
>>I'm using ony pg_autovacuum. I expect that disk usage will reach
>>a steady state but is not. PG engine: 7.4.5
>
>
> One data point doesn't prove that you're not at a steady state.

I do a graph about my disk usage and it's a ramp since one week,
I'll continue to wait in order to see if it will decrease.
I was expecting the steady state at something like 4 GB
( after a full vacuum and reindex ) + 10 % = 4.4 GB
I'm at 4.6 GB and increasing. I'll see how it will continue.

>># vacuum full verbose messages;
>>INFO:  vacuuming "public.messages"
>>INFO:  "messages": found 77447 removable, 1606437 nonremovable row versions in 69504 pages
>>...
>>INFO:  "messages": moved 55221 row versions, truncated 69504 to 63307 pages
>
>
> 10% overhead sounds fairly reasonable to me.  How does that compare to
> the amount of updating you do on the table --- ie, do you turn over 10%
> of the table in a day?

Less, that table have 1.6 milion rows, and I insert 2000 rows in a day
with almost ~ 40000 update in one day. So it's something like: 2.5 %


Regards
Gaetano Mendola







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