Re: Stefan's bug (was: max_standby_delay considered harmful)

On Mon, May 24, 2010 at 1:27 AM, Fujii Masao <masao.fujii@gmail.com> wrote:
> On Wed, May 19, 2010 at 2:47 PM, Fujii Masao <masao.fujii@gmail.com> wrote:
>>>> Oh, right. How about allowing the postmaster only in PM_STARTUP,
>>>> PM_RECOVERY, PM_HOT_STANDBY or PM_WAIT_READONLY state to invoke
>>>> walreceiver? We can keep walreceiver alive until all read only
>>>> backends have gone, and prevent unexpected startup of walreceiver.
>>>
>>> Yes, that seems like something we should be checking, if we aren't already.
>>
>> I'll do that.
>
> Here is the updated version. I added the above-mentioned check
> into the patch.

This looks pretty reasonable to me, but I guess I feel like it would
be better to drive the CancelBackup() decision off of whether we've
ever reached PM_RUN rather than consulting XLogCtl.  It just feels
cleaner to me to drive all of the postmaster decisions off of the same
signalling mechanism rather than having a separate one (that only
works because it's used very late in shutdown when we theoretically
don't need a lock) just for this one case.

I could be all wet, though.

-- 
Robert Haas
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