Re: reducing the overhead of frequent table locks, v4

From: Jeff Davis <pgsql(at)j-davis(dot)com>
To: Robert Haas <robertmhaas(at)gmail(dot)com>
Cc: "pgsql-hackers(at)postgresql(dot)org" <pgsql-hackers(at)postgresql(dot)org>
Subject: Re: reducing the overhead of frequent table locks, v4
Date: 2011-07-12 17:02:01
Message-ID: 1310490121.3012.274.camel@jdavis
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On Tue, 2011-07-12 at 07:55 -0500, Robert Haas wrote:
> I haven't been that worried about overflow of the fast path table. If
> you are locking more than 16 relations at once, you probably have at
> least 5 tables in the query, maybe more - it depends in how many
> indexes you have, of course. My assumption has been that at that
> point you're going to spend enough time planning and executing the
> query that the lock manager will no longer be a major bottleneck. Of
> course, there might be cases where that isn't so.

Yeah, I think you're right here. It's probably not much of a practical
concern.

I was slightly bothered because it seemed a little unpredictable. But it
seems very minor, and if we wanted to fix it later I think we could.

Regards,
Jeff Davis

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