Re: pgbench: make verbose error messages thread-safe

On 4/24/26 2:26 PM, Fujii Masao wrote:
> Hi,
>
> While running pgbench with multiple threads and --verbose-errors,
> I found that some verbose error messages were corrupted.
> This issue happens because printVerboseErrorMessages() uses
> a function-local static PQExpBuffer for building those messages.
> Since that buffer is shared across threads, it is not thread-safe.
>
> Attached patch fixes this issue by changing printVerboseErrorMessages()
> to use a local PQExpBufferData instead of a static one. Thoughts?
>
> Since this issue was introduced in v15, the patch should be
> backpatched to v15 if accepted.
>
> Regards,
>
In single-threaded mode, reusing the static local buffer might be
slightly more performant. But if this function needs to be safe in
multi-threaded mode, then we have to stop using a static local variable.

So the change looks reasonable and good to me.

Regards,
Alex Guo