Re: FATAL: bogus data in lock file "postmaster.pid": "" - Mailing list pgsql-hackers

From Magnus Hagander
Subject Re: FATAL: bogus data in lock file "postmaster.pid": ""
Date
Msg-id CABUevEwhH22SHK2aCJVWM75UG0QHLL9D+mGPaqt=XtGYDagVkw@mail.gmail.com
Whole thread Raw
In response to Re: FATAL: bogus data in lock file "postmaster.pid": ""  (Tom Lane <tgl@sss.pgh.pa.us>)
Responses Re: FATAL: bogus data in lock file "postmaster.pid": ""  (Michael Beattie <mtbeedee@gmail.com>)
List pgsql-hackers
On Thu, Jan 5, 2012 at 23:19, Tom Lane <tgl@sss.pgh.pa.us> wrote:
> Magnus Hagander <magnus@hagander.net> writes:
>> On Thu, Jan 5, 2012 at 17:13, Tom Lane <tgl@sss.pgh.pa.us> wrote:
>>> I think link(2) would create race conditions of its own.  I'd be
>>> inclined to suggest that maybe we should just special-case a zero length
>>> postmaster.pid file as meaning "okay to proceed".  In general, garbage
>
>> That's pretty much what I meant - but with a warning message.
>
> Actually ... wait a minute.  If we allow that, don't we create a race
> condition between two postmasters starting at almost the same instant?
> The second one could see the lock file when the first has created but
> not yet filled it.

Good point, yeah, it should do that. But I still think it's rare
enough that just special-casing the error message should be enough...

--
 Magnus Hagander
 Me: http://www.hagander.net/
 Work: http://www.redpill-linpro.com/


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