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Re: select_parallel test failure: gather sometimes losing tuples(maybe during rescans)? - Mailing list pgsql-hackers

From Thomas Munro
Subject Re: select_parallel test failure: gather sometimes losing tuples(maybe during rescans)?
Date
Msg-id CAEepm=1=+yxVLw-yX7jP1Jc7Z8a-mW_xNBPAjRBKRwk+ZJ4mYw@mail.gmail.com
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In response to Re: select_parallel test failure: gather sometimes losing tuples(maybe during rescans)?  (Tomas Vondra <tomas.vondra@2ndquadrant.com>)
Responses Re: select_parallel test failure: gather sometimes losing tuples(maybe during rescans)?  (Thomas Munro <thomas.munro@enterprisedb.com>)
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On Sun, Mar 4, 2018 at 4:17 PM, Tomas Vondra
<tomas.vondra@2ndquadrant.com> wrote:
> On 03/04/2018 04:11 AM, Thomas Munro wrote:
>> On Sun, Mar 4, 2018 at 4:07 PM, Tomas Vondra
>> <tomas.vondra@2ndquadrant.com> wrote:
>>> ! ERROR:  lost connection to parallel worker
>>
>> That sounds like the new defences from 2badb5afb89cd569500ef7c3b23c7a9d11718f2f.
>
> Yeah. But I wonder why the worker fails at all, or how to find that.

Could it be that a concurrency bug causes tuples to be lost on the
tuple queue, and also sometimes causes X (terminate) messages to be
lost from the error queue, so that the worker appears to go away
unexpectedly?

-- 
Thomas Munro
http://www.enterprisedb.com

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