Subject: Re: Autovacuum of pg_shdepend
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Date: Wed, 3 Aug 2016 01:02:08 +0200
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Dne 4.5.2016 v 22:08 Ondřej Světlík napsal(a):
> Dne 4.5.2016 v 20:52 Victor Yegorov napsal(a):
>> 2016-05-04 18:08 GMT+03:00 Ondřej Světlík <osvetlik@flexibee.eu
>> <mailto:osvetlik@flexibee.eu>>:
>>
>>     we have a strange problem with autovacuum. We have three workers,
>>     but usually only one works and two are waiting as they are all
>>     trying to process table pg_shdepend which is shared between all
>>     databases.
>>
>>
>> I hit the same issue when we've migrated out all large objects (~200Gb
>> total), I've executed `vacuumlo` and then all autovacuums started to
>> process `pg_shdepend`.
>> They've been picking on this table over and over again from different
>> databases, but were stopping on the truncation phase due to other
>> autovacuums were waiting on the same table.
>>
>> I ended up manually vacuuming this table in the database, that was
>> cleaned up, and also in the `postgres` DB. It fixed the case for me.
>> This was on 9.0.23 though.
>>
>> --
>> Victor Y. Yegorov
>
> Thank you very much, we have a working autovacuum on one of our clusters
> again. That's awesome :-).
>
> Ondřej


Hello again,

as this is still not fixed in any released version and the problem 
occurred again, let me ask one question. Which form of manual VACUUM is 
sufficient to prevent wraparound? Is it VACUUM FREEZE or do I have to 
use VACUUM FULL?

Thanks in advance,

Ondřej


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