Message-ID: <4EF28B8A.1060602@gmail.com>
Date: Thu, 22 Dec 2011 09:44:42 +0800
From: Rural Hunter <ruralhunter@gmail.com>
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To: Kevin Grittner <kevin.grittner@wicourts.gov>
CC: Jerry Sievers <gsievers19@comcast.net>, pgsql-admin@postgresql.org,
	berto.d.sera@gmail.com
Subject: Re: lock problem
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	<4EF1F027.507@gmail.com> <87aa6m7xqz.fsf@comcast.net>
	<CAKwGa__-7ncap5sji9x0=3g5V=Fv1cpZYGO5bKDHgxeT6z9rzg@mail.gmail.com>
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	<4EF1B04D0200002500043F4C@gw.wicourts.gov>
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hmm....no I didn't do anything. is the lock priority decided by OS not 
the DB? I'm confused here. B/C/D started several mins later than A here 
while the update statement takes no more than 1 second. of coz there 
are hundreds of connections trying to acquire the lock during that 
time.

于2011年12月22日 0:09:17,Kevin Grittner写到:
> Rural Hunter<ruralhunter@gmail.com>  wrote:
>
>> I still have this question:
>> same statement A,B,C,D update same row. The start order is
>> A->B->C-D.  From what I've gotten, B/C/D got the lock before A.
>> Why did that happen?
>
> Did you do anything to prevent it from happening?  If not, the OS
> scheduler is going to give time to one process or another in a
> fairly unpredictable way.
>
> -Kevin
>