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Re: Suggestion to add --continue-client-on-abort option to pgbench

Fujii Masao <masao.fujii@gmail.com>

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From: Fujii Masao <masao.fujii@gmail.com>
To: Chao Li <li.evan.chao@gmail.com>
Cc: Rintaro Ikeda <ikedarintarof@oss.nttdata.com>, Yugo Nagata <nagata@sraoss.co.jp>, Jakub Wartak <jakub.wartak@enterprisedb.com>, "Hayato Kuroda (Fujitsu)" <kuroda.hayato@fujitsu.com>, "slpmcf@gmail.com" <slpmcf@gmail.com>, "boekewurm+postgres@gmail.com" <boekewurm+postgres@gmail.com>, "pgsql-hackers@postgresql.org" <pgsql-hackers@postgresql.org>, Srinath Reddy Sadipiralla <srinath2133@gmail.com>, Dilip Kumar <dilipbalaut@gmail.com>
Date: 2025-11-07T09:33:17Z
Lists: pgsql-hackers 
On Fri, Nov 7, 2025 at 9:07 AM Chao Li <li.evan.chao@gmail.com> wrote:
> If you put this explanation to the inline comment, things would get clearer. But based on this explanation, I just got the other doubt. When a pipeline is aborted, res is NULL, but we still stay in the for loop, PQClear(res) will do nothing, then the “for” loop is similar to an empty loop, would that lead to a high CPU usage? From this perspective, when pipeline is aborted, while waiting for PIPELINE_SYNC, adding a tiny sleep might be better.

You're concerned about cases where the server response is delayed,
causing the pipeline status to take time to reach PIPELINE_SYNC, right?
In that situation, since discardAvailableResults() waits on PQgetResult(),
it shouldn't enter a busy loop, correct?


> I will back to work next Monday, then I will try to run a test and reproduce the scenario of pipeline abort.

I plan to commit the patch soon, but let's keep discussing and
investigating the case you mentioned afterward!

Regards,

-- 
Fujii Masao

Commits

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

  1. pgbench: Fix assertion failure with multiple \syncpipeline in pipeline mode.

  2. pgbench: Add --continue-on-error option.

  3. Fix "inconsistent DLL linkage" warning on Windows MSVC

  4. pgbench: Fix error reporting in readCommandResponse().

  5. pgbench: Fix assertion failure with retriable errors in pipeline mode.

  6. Allow pgbench to retry in some cases.