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Date: Fri, 18 Jul 2014 04:01:13 +1000
Subject: Re: Blocked thread
From: Chris Angelico <rosuav@gmail.com>
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On Fri, Jul 18, 2014 at 3:55 AM, Larry Martell <larry.martell@gmail.com> wrote:
> I can have as many connections to the db server as I want, that's not
> the issue. The issue is that my main thread seems to be blocked in the
> join(), so I guess I'm going to need a separate script. I was trying
> to avoid that.

Right, but what you're trying to do is monitor the local thread, by
spinning off a thread to do the deletion and then keeping an eye on it
by attempting a timed join. I'm saying it'd probably be easier to do
the monitoring on the server end, via a second connection. (It most
likely doesn't need special database privileges, even; at least in
PostgreSQL, any user can see pg_stat_activity entries for the same
user.) That's usually going to be more reliable, plus the server can
tell you whether the deletion is blocked waiting for a lock or busy
writing to the disk or something else.

ChrisA