Re: Reorderbuffer crash during recovery

On Thu, Nov 07, 2019 at 11:01:17AM +0530, Dilip Kumar wrote:
>On Thu, Nov 7, 2019 at 9:55 AM vignesh C <vignesh21(at)gmail(dot)com> wrote:
>>
>> On Wed, Nov 6, 2019 at 5:41 PM Dilip Kumar <dilipbalaut(at)gmail(dot)com> wrote:
>> >
>> > On Wed, Nov 6, 2019 at 5:20 PM vignesh C <vignesh21(at)gmail(dot)com> wrote:
>> > >
>> > > Hi,
>> > >
>> > > ...
>> > >
>> > > Issue1 it seems like if all the reorderbuffer has been flushed and
>> > > then the server restarts. This problem occurs.
>> > > Issue 2 it seems like if there are many subtransactions present and
>> > > then the server restarts. This problem occurs. The subtransaction's
>> > > final_lsn is not being set and when ReorderBufferRestoreCleanup is
>> > > called the assert fails. May be for this we might have to set the
>> > > subtransaction's final_lsn before cleanup(not sure).
>> > >
>> > > I could not reproduce this issue consistently with a test case, But I
>> > > felt this looks like a problem from review.
>> > >
>> > > For issue1, I could reproduce by the following steps:
>> > > 1) Change ReorderBufferCheckSerializeTXN so that it gets flushed always.
>> > > 2) Have many open transactions with subtransactions open.
>> > > 3) Attach one of the transaction from gdb and call abort().
>> >
>> > Do you need subtransactions for the issue1? It appears that after the
>> > restart if the changes list is empty it will hit the assert. Am I
>> > missing something?
>> >
>>
>> When I had reported this issue I could reproduce this issue with
>> sub-transactions. Now I have tried without using sub-transactions and
>> could still reproduce this issue. You are right Issue 1 will appear in
>> both the cases with and without subtransactions.
>
>Okay, thanks for the confirmation.
>

I'm a bit confused - does this happen only with the logical_work_mem
patches, or with clean master too? If only with the patches, which
version exactly?

regards

--
Tomas Vondra http://www.2ndQuadrant.com
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