Re: vacuum as flags in PGPROC - Mailing list pgsql-patches

From Heikki Linnakangas
Subject Re: vacuum as flags in PGPROC
Date
Msg-id 471F6B86.8090209@enterprisedb.com
Whole thread Raw
In response to Re: vacuum as flags in PGPROC  (Tom Lane <tgl@sss.pgh.pa.us>)
List pgsql-patches
Tom Lane wrote:
> Heikki Linnakangas <heikki@enterprisedb.com> writes:
>> Alvaro Herrera wrote:
>>> I did it that way (i.e. added locking) and then realized that it
>>> shouldn't really be a problem, because the only one who can be setting
>>> vacuum flags is the process itself.  Other processes can only read the
>>> flags.
>
>> It would still be a problem if there was any other fields that were
>> updated by other processes, adjacent to the vacuum flags. I don't think
>> that's the case, however.
>
> Well, that may not be the case today, but it still seems like an
> assumption that will come back to bite us someday.  And can you imagine
> trying to debug a misbehavior like that?  It's really not worth the risk,
> given how seldom these flags will be changed.

Oh, I totally agree. I wasn't trying to argue to the contrary.

--
  Heikki Linnakangas
  EnterpriseDB   http://www.enterprisedb.com

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