Re: [PATCH] Refactoring of LWLock tranches - Mailing list pgsql-hackers

From Robert Haas
Subject Re: [PATCH] Refactoring of LWLock tranches
Date
Msg-id CA+TgmoZAJsnSYFzCywFdDJOKE=K-M3B6vcyaYVkH+qF4cYoCvQ@mail.gmail.com
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In response to Re: [PATCH] Refactoring of LWLock tranches  (Ildus Kurbangaliev <i.kurbangaliev@postgrespro.ru>)
Responses Re: [PATCH] Refactoring of LWLock tranches  (Ildus Kurbangaliev <i.kurbangaliev@postgrespro.ru>)
List pgsql-hackers
On Fri, Nov 20, 2015 at 6:53 AM, Ildus Kurbangaliev
<i.kurbangaliev@postgrespro.ru> wrote:
> We keep limited number of LWLocks in base shared memory, why not keep
> their thanches in shared memory too? Other tranches can be in local
> memory, we just have to save somewhere highest id of these tranches.

I just don't see it buying us anything.  The tranches are small and
contain only a handful of values.  The values need to be present in
shared memory but the tranches themselves don't.

Now, if it's convenient to put them in shared memory and doesn't cause
us any other problems, then maybe there's no real downside.  But it's
not clear to me that there's any upside either.

-- 
Robert Haas
EnterpriseDB: http://www.enterprisedb.com
The Enterprise PostgreSQL Company



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