Re: logical decoding : exceeded maxAllocatedDescs for .spill files

Amit Khandekar <amitdkhan.pg@gmail.com>

From: Amit Khandekar <amitdkhan.pg@gmail.com>
To: Amit Kapila <amit.kapila16@gmail.com>
Cc: Andres Freund <andres@anarazel.de>, Tom Lane <tgl@sss.pgh.pa.us>, Thomas Munro <thomas.munro@gmail.com>, Robert Haas <robertmhaas@gmail.com>, Tomas Vondra <tomas.vondra@2ndquadrant.com>, Alvaro Herrera from 2ndQuadrant <alvherre@alvh.no-ip.org>, PostgreSQL Hackers <pgsql-hackers@lists.postgresql.org>
Date: 2019-11-18T12:20:22Z
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 →
  1. When a TAP file has non-zero exit status, retain temporary directories.

  2. Fix running out of file descriptors for spill files.

  3. Track statistics for spilling of changes from ReorderBuffer.

  4. Handle ReadFile() EOF correctly on Windows.

  5. Add logical_decoding_work_mem to limit ReorderBuffer memory usage.

  6. Generational memory allocator

  7. Support retaining data dirs on successful TAP tests

On Mon, 18 Nov 2019 at 17:20, Amit Kapila <amit.kapila16@gmail.com> wrote:
> I see that you have made changes in ReorderBufferRestoreChanges to use
> PathNameOpenFile, but not in ReorderBufferSerializeTXN.  Is there a
> reason for the same?  In my test environment, with the test provided
> by you, I got the error (reported in this thread) via
> ReorderBufferSerializeTXN.

You didn't get this error with the patch applied, did you ?

If you were debugging this without the patch applied, I suspect that
the reason why ReorderBufferSerializeTXN() => OpenTransientFile() is
generating this error is because the max limit must be already crossed
because of earlier calls to ReorderBufferRestoreChanges().

Note that in ReorderBufferSerializeTXN(), OpenTransientFile() is
sufficient because the code in that function has made sure the fd gets
closed there itself.

If you are getting this error even with the patch applied, then this
needs investigation.

-- 
Thanks,
-Amit Khandekar
EnterpriseDB Corporation
The Postgres Database Company