On Wed, Sep 10, 2014 at 5:35 PM, Etsuro Fujita <fujita.ets...@lab.ntt.co.jp> wrote: > (2014/09/10 12:31), Fujii Masao wrote: >> >> On Wed, Sep 10, 2014 at 12:15 PM, Etsuro Fujita >> <fujita.ets...@lab.ntt.co.jp> wrote: >>> >>> (2014/09/09 22:17), Fujii Masao wrote: >>>> >>>> Attached is the updated version of the patch. > > >>> I took a quick review on the patch. It looks good to me, > > >>> but one thing I'm >>> concerned about is >>> >>> You wrote: >>>>>>> >>>>>>> The attached patch introduces the GIN index storage parameter >>>>>>> "PENDING_LIST_CLEANUP_SIZE" which specifies the maximum size of >>>>>>> GIN pending list. If it's not set, work_mem is used as that maximum >>>>>>> size, >>>>>>> instead. So this patch doesn't break the existing application which >>>>>>> currently uses work_mem as the threshold of cleanup operation of >>>>>>> the pending list. It has only not to set PENDING_LIST_CLEANUP_SIZE. >>> >>> >>> As you mentioned, I think it's important to consider for the existing >>> applications, but I'm wondering if it would be a bit confusing users to >>> have >>> two parameters, >> >> >> Yep. >> >>> PENDING_LIST_CLEANUP_SIZE and work_mem, for this setting. >>> Wouldn't it be easy-to-use to have only one parameter, >>> PENDING_LIST_CLEANUP_SIZE? How about setting PENDING_LIST_CLEANUP_SIZE >>> to >>> work_mem as the default value when running the CREATE INDEX command? >> >> >> That's an idea. But there might be some users who want to change >> the cleanup size per session like they can do by setting work_mem, >> and your idea would prevent them from doing that... > > > Why not use ALTER INDEX ... SET (PENDING_LIST_CLEANUP_SIZE= ...)? Maybe I'm > missing something, though.
It takes AccessExclusive lock and has an effect on every sessions (not only specified session). Regards, -- Fujii Masao -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers
