Firebird5 added config

[ryousuke hayami]

Hello!

Firebird5 added configuration to firebird.conf.

#OuterJoinConversion
#MaxStatementCacheSize
#MaxParallelWorkers
#parallel worker

I'm having trouble figuring out how to set each.
Are there any guidelines?

It is assumed that 1 to 20 people will connect using Windows.

Best Regards,
hayami

[Mark Rotteveel]

`OuterJoinConversion` should be left at its default setting (true). This
is intended as a temporary workaround if you have queries that have a
bad regression due to this change in the optimizer, and you can't
rewrite the query to fix the issue. I'd also say that if you have a
reason to set this to false, you should report a bug with a reproduction
script/database that demonstrates the performance regression.

I'd leave `MaxStatementCacheSize` at its default (2M) for now. It's per
attachment, so with 10 connections, that means it will take 20 MiB. You
could always try to increase it to see if your application benefits from
a larger cache, but I wouldn't get hung up on it.

I'd say, increase `MaxParallelWorkers` from its default of 1 to say 8,
up to the number of CPU cores of your server, and `ParallelWorkers` to 2
- 4.

Mark
--
Mark Rotteveel

[ryousuke hayami]

Thank you for answering.

I would like to set it conservatively as shown below and see how it goes.

#MaxParallelWorkers = 4
#ParallelWorkers = 2

2024年1月25日木曜日 16:53:58 UTC+9 ma...@lawinegevaar.nl:

[ryousuke hayami]

Hi.

About ParallelWorkers.
The calculation tool yielded the following results.

What do you think that means?

> ParallelWorkers = 1 # default parallel threads
> MaxParallelWorkers = 64 # parallel threads for sweep, backup, restore

2024年1月30日火曜日 9:49:33 UTC+9 ryousuke hayami:

[Alexey Kovyazin]

Hello,

ParallelWorkers = 1  implies that better use explicit parameter -par NN, when you need to use gbak or gfix tool.

See example of gbak with -par here:

https://ib-aid.com/articles/firebird-gbak-backup-tips-and-tricks#110hqbirdbackup

MaxParallelForks is set to 64 to avoid exhaustion of available parallel workers in case of several parallel operations at once.

Regards,

Alexey Kovyazin

вторник, 19 марта 2024 г. в 02:55:56 UTC+1, ryousuke hayami: