Re: [PATCH] Fix severe performance regression with gettext 0.20+ on Windows

On 12/12/2025 2:01 PM, Tom Lane wrote:
> Bryan Green <dbryan(dot)green(at)gmail(dot)com> writes:
>> On 12/11/2025 8:43 AM, Peter Eisentraut wrote:
>>> I wonder, this change that gettext did with the locale naming, does that
>>> also affect what guidance we need to provide to users about how to
>>> configure locale names?  For example, on a Unix-ish system, a user can
>>> do something like initdb ... --lc-messages=de_DE.  What locale name
>>> format do you need to use on Windows to get the translations to
>>> activate?  Does this also depend on the gettext version?
>
>> If the language catalogue is installed then they will get translated
>> messages as expected. The downside is that because they are passing a
>> posix locale name then gettext will still do the enumeration everytime.
>> This will have the negative performance impact. The good news is that
>> gettext has accepted my cache patch for their next release. If a
>> Windows system is configured with lc_messages="de_DE", but has the next
>> release of gettext-- they should be fine. If they don't have the next
>> release of gettext-- they will notice the performance issue, but that
>> can be fixed by just changing to from "de_DE" to the correct Windows
>> locale name.
>
> So IIUC, POSIX-style lc_messages settings do still work on Windows and
> will continue to do so, they just incur some extra overhead with
> current gettext versions?
>
> If that's the case, I'm inclined to leave my NLS-testing patch [1] as-is,
> unconditionally setting a POSIX lc_messages value. I had anticipated
> adding some logic to it to select a Windows locale name when on
> Windows, but that seems rather messy, and it's not even clear that the
> test would net out faster. It only needs to do a dozen or so message
> lookups, which has to be set against the time needed to identify what
> platform we are running on.
>
> regards, tom lane
>
> [1] https://www.postgresql.org/message-id/1038674.1765568967%40sss.pgh.pa.us
Correct. The translation done for 1M exceptions is what was used as a
benchmark. That turns into a few million calls to gettext. Your case
seems like it would not really notice the difference.

--
Bryan Green
EDB: https://www.enterprisedb.com