Re: Good name for new lock type for VACUUM? - Mailing list pgsql-hackers

From Hiroshi Inoue
Subject Re: Good name for new lock type for VACUUM?
Date
Msg-id 3B369710.894DA7A2@tpf.co.jp
Whole thread Raw
In response to Re: Good name for new lock type for VACUUM?  (Bruce Momjian <pgman@candle.pha.pa.us>)
List pgsql-hackers
Tom Lane wrote:
> 
> Bruce Momjian <pgman@candle.pha.pa.us> writes:
> >> Still, it's an interesting alternative.  Comments anyone?
> 
> > SelfExclusiveLock is clear and can't be confused with other lock types.
> 
> It could possibly be made a little less dangerous if "SelfExclusiveLock"
> were defined to conflict with itself and AccessExclusiveLock (and
> nothing else).  That would at least mean that holding SelfExclusiveLock
> would guarantee the table not go away under you; so there might be
> scenarios where holding just that lock would make sense.
> 
> Still, I'm not sure that this lock type is as flexible as it seems at
> first glance. 

I don't think "SelfExclusiveLock" is an excellent lock either.
However it seems to point out the reason why we couldn't
place(name) "VacuumLock" properly in our locking system.

regards,
Hiroshi Inoue


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