Re: logical decoding : exceeded maxAllocatedDescs for .spill files

Kuntal Ghosh <kuntalghosh.2007@gmail.com>

From: Kuntal Ghosh <kuntalghosh.2007@gmail.com>

To: Amit Kapila <amit.kapila16@gmail.com>

Cc: Tom Lane <tgl@sss.pgh.pa.us>, Tomas Vondra <tomas.vondra@2ndquadrant.com>, Noah Misch <noah@leadboat.com>, Amit Khandekar <amitdkhan.pg@gmail.com>, Alvaro Herrera from 2ndQuadrant <alvherre@alvh.no-ip.org>, Andres Freund <andres@anarazel.de>, Juan José Santamaría Flecha <juanjo.santamaria@gmail.com>, PostgreSQL Hackers <pgsql-hackers@lists.postgresql.org>, Robert Haas <robertmhaas@gmail.com>, Thomas Munro <thomas.munro@gmail.com>

Date: 2020-02-07T12:01:47Z

Lists: pgsql-hackers

Commits

Same data as JSON: GET /api/v1/messages/:b64id/commits the thread's linked commits as JSON, with link sources. API reference →

When a TAP file has non-zero exit status, retain temporary directories.
- 048c7ccd7d6d 9.6.17 landed
- d8efc5900f7c 10.12 landed
- 887657d183fc 11.7 landed
- 78a26c3edd85 12.2 landed
- bf989aaf3561 13.0 landed
Fix running out of file descriptors for spill files.
- 1ad47e8757bb 9.4.26 landed
- a6f4f407ada0 9.5.21 landed
- 27b5f48c79f7 10.12 landed
- 3e3a79735235 11.7 landed
- f8a6d8e71b17 12.2 landed
- d20703805383 13.0 landed
- ba5b4e506489 9.6.17 landed
Track statistics for spilling of changes from ReorderBuffer.
- 9290ad198b15 13.0 cited
Handle ReadFile() EOF correctly on Windows.
- 2189f49c420f 12.2 landed
- 6969deeb8d39 13.0 landed
Add logical_decoding_work_mem to limit ReorderBuffer memory usage.
- cec2edfa7859 13.0 cited
Generational memory allocator
- a4ccc1cef5a0 11.0 cited
Support retaining data dirs on successful TAP tests
- 90627cf98a8e 11.0 cited

Attachments

0001-Restrict-memory-allocation-in-reorderbuffer-context.patch (application/octet-stream) patch 0001

On Tue, Feb 4, 2020 at 2:40 PM Amit Kapila <amit.kapila16@gmail.com> wrote:
>
> I don't think we can just back-patch that part of code as it is linked
> to the way we are maintaining a cache (~8MB) for frequently allocated
> objects.  See the comments around the definition of
> max_cached_tuplebufs.  But probably, we can do something once we reach
> such a limit, basically, once we know that we have already allocated
> max_cached_tuplebufs number of tuples of size MaxHeapTupleSize, we
> don't need to allocate more of that size.  Does this make sense?
>

Yeah, this makes sense. I've attached a patch that implements the
same. It solves the problem reported earlier. This solution will at
least slow down the process of going OOM even for very small sized
tuples.



-- 
Thanks & Regards,
Kuntal Ghosh
EnterpriseDB: http://www.enterprisedb.com