Re: Re: [COMMITTERS] pgsql: Add some isolation tests for deadlock detection and resolution. - Mailing list pgsql-hackers

From Robert Haas
Subject Re: Re: [COMMITTERS] pgsql: Add some isolation tests for deadlock detection and resolution.
Date
Msg-id CA+TgmoYFg+ut1OOHfjCGgzpZtrbZ-nTEf8wQ_4+oVKO+PudFjQ@mail.gmail.com
Whole thread Raw
In response to Re: Re: [COMMITTERS] pgsql: Add some isolation tests for deadlock detection and resolution.  (Tom Lane <tgl@sss.pgh.pa.us>)
List pgsql-hackers
On Thu, Feb 11, 2016 at 12:04 PM, Tom Lane <tgl@sss.pgh.pa.us> wrote:
> I wrote:
>> No, because the machines that are failing are showing a "<waiting ...>"
>> annotation that your reference output *doesn't* have.  I think what is
>> actually happening is that these machines are seeing the process as
>> waiting and reporting it, whereas on your machine the backend detects
>> the deadlock and completes the query (with an error) before
>> isolationtester realizes that the process is waiting.
>
> I confirmed this theory by the expedient of changing the '10ms' setting
> in the test script to 1ms (which worked) and 100ms (which did not, on
> the same machine).
>
> I've committed an update that adjusts the timeouts to hopefully ensure
> that isolationtester always sees the query as blocked before the deadlock
> detector unblocks it; which seems like the behavior we want to test for,
> anyway.

Thanks.  I really appreciate it.

-- 
Robert Haas
EnterpriseDB: http://www.enterprisedb.com
The Enterprise PostgreSQL Company



pgsql-hackers by date:

Previous
From: Amit Kapila
Date:
Subject: Re: [PATCH] Refactoring of LWLock tranches
Next
From: Robert Haas
Date:
Subject: Re: Performance degradation in commit ac1d794