Re: [HACKERS] Inefficiency in recent pgtz patch

Started by Magnus Haganderabout 21 years ago2 messagespatches
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#1Magnus Hagander
magnus@hagander.net

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

Attachments:

tzcache.patchapplication/octet-stream; name=tzcache.patchDownload+17-17
#2Bruce Momjian
bruce@momjian.us
In reply to: Magnus Hagander (#1)

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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