Re: PATCH: logical_work_mem and logical streaming of large in-progress transactions

On 12/23/2017 03:03 PM, Erikjan Rijkers wrote:
> On 2017-12-23 05:57, Tomas Vondra wrote:
>> Hi all,
>>
>> Attached is a patch series that implements two features to the logical
>> replication - ability to define a memory limit for the reorderbuffer
>> (responsible for building the decoded transactions), and ability to
>> stream large in-progress transactions (exceeding the memory limit).
>>
>
> logical replication of 2 instances is OK but 3 and up fail with:
>
> TRAP: FailedAssertion("!(last_lsn < change->lsn)", File:
> "reorderbuffer.c", Line: 1773)
>
> I can cobble up a script but I hope you have enough from the assertion
> to see what's going wrong...

The assertion says that the iterator produces changes in order that does
not correlate with LSN. But I have a hard time understanding how that
could happen, particularly because according to the line number this
happens in ReorderBufferCommit(), i.e. the current (non-streaming) case.

So instructions to reproduce the issue would be very helpful.

Attached is v2 of the patch series, fixing two bugs I discovered today.
I don't think any of these is related to your issue, though.

regards

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