[pgpool-hackers: 4326] Re: minimal parser and multi-statement query

[Muhammad Usama]

Hi Ishii San,

The patch looks good, and I believe the approach covers the performance
concerns.

Thanks
Best regards
Muhammad Usama


On Sat, Apr 15, 2023 at 5:06 AM Tatsuo Ishii <ishii at sraoss.co.jp> wrote:

> >> On 14-Apr-2023, at 5:37 PM, Tatsuo Ishii <ishii at sraoss.co.jp> wrote:
> >>
> >> Hi Usama,
> >>
> >>> Thanks for conducting the tests.
> >>
> >> No prolem.
> >>
> >>> 3-4 % seems quite a significant degradation. So one possible way would
> bet
> >>> retire the
> >>> minimal parser and always use the standard parser so that we can save
> the
> >>> extra scanning
> >>> needed for the detection of multi-statement queries.
> >>>
> >>> It (removing minimal parser altogether) may be less of a performance
> >>> overhead than this. What is your opinion?
> >>
> >> Is it possible to run the extra scanning only for lengthy queries(say,
> >> longer than 10k)? i.e.
> >>
> >> If (lengthy query)
> >>  extra scanning;
> >>  if (single-statement)
> >>    minimal_parser = true;
> >>  else
> >>    minimal_parser = false;
> >> else
> >>  minimal_parser = false;
> >> fi
> >> raw_parser (minimal_parser);
> >>
> >> With this, we can avoid the extra scanning for most queries. I think
> >> the minimal parser is best for lengthy queries.
> >>
> >
> > Agreed, I guess that makes total sense
>
> Attached is a patch for this direction. What do you think?
>
> Best reagards,
> --
> Tatsuo Ishii
> SRA OSS LLC
> English:
> https://url.avanan.click/v2/___http://www.sraoss.co.jp/index_en/___.YXAzOnBlcmNvbmE6YTpnOjNmMjQwMWRlZTIzYjlkODcyYWYyNTNkNWQ0ZmNjMjg0OjY6M2ZiYjo0ZDAzZjNiODFhNDhiMTA0MTdiMjBmOGJlOTA5YjBmZDEyYmZmNjM4YzRlYjQ5MWM3NDY3YzhhNjhiZDY3NDViOnA6VA
> Japanese:
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>
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