Thread: Re: [HACKERS] Inefficiency in recent pgtz patch

Re: [HACKERS] Inefficiency in recent pgtz patch

From
"Magnus Hagander"
Date:
>> Do you agree that using a hashtable for it in general is a good idea
>> assuming this sideeffect is removed, though?
>
>I have no problem with the hashtable, only with preloading it with
>everything.  What I'd like to see is that the table inherited at fork()
>contains just the data for the default timezone.  (At least in the
>normal case where that setting hasn't been changed since postmaster
>start.)

Here's a patch doing this. Changes score_timezone not to use pg_tzset(),
and thus not loading all the zones in the cache. The actual timezone
being picked will be set using set_global_timezone() which in turn calls
pg_tzset() and loads it in the cache.


//Magnus

Attachment

Re: [HACKERS] Inefficiency in recent pgtz patch

From
Bruce Momjian
Date:
Patch applied.  Thanks.

---------------------------------------------------------------------------

Magnus Hagander wrote:
> >> Do you agree that using a hashtable for it in general is a good idea
> >> assuming this sideeffect is removed, though?
> >
> >I have no problem with the hashtable, only with preloading it with
> >everything.  What I'd like to see is that the table inherited at fork()
> >contains just the data for the default timezone.  (At least in the
> >normal case where that setting hasn't been changed since postmaster
> >start.)
>
> Here's a patch doing this. Changes score_timezone not to use pg_tzset(),
> and thus not loading all the zones in the cache. The actual timezone
> being picked will be set using set_global_timezone() which in turn calls
> pg_tzset() and loads it in the cache.
>
>
> //Magnus

Content-Description: tzcache.patch

[ Attachment, skipping... ]

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