Re: [PATCH] Refactoring of LWLock tranches

On Wed, Sep 23, 2015 at 11:22 AM, Alvaro Herrera
<alvherre(at)2ndquadrant(dot)com> wrote:
> Robert Haas wrote:
>> On Tue, Sep 22, 2015 at 5:16 AM, Ildus Kurbangaliev
>> <i(dot)kurbangaliev(at)postgrespro(dot)ru> wrote:
>> > Yes, probably.
>> > I'm going to change API calls as you suggested earlier.
>> > How you do think the tranches registration after initialization should
>> > look like?
>>
>> I don't see any need to change anything there. The idea there is that
>> an extension allocates a tranche ID and are responsible for making
>> sure that every backend that uses that tranche finds out about the ID
>> that was chosen and registers a matching tranche definition. How to
>> do that is the extension's problem. Maybe eventually we'll provide
>> some tools to make that easier, but that's separate from the work
>> we're trying to do here.
>
> FWIW I had assumed, when you created the tranche stuff, that SLRU users
> would all allocate their lwlocks from a tranche provided by slru.c
> itself, and the locks would be stored in the slru Ctl struct. Does that
> not work for some reason?

I think that should work and that it's a good idea. I think it's just
a case of nobody having done the work.

--
Robert Haas
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