Re: [PATCH] pg_isready (was: [WIP] pg_ping utility)

On Wed, Jan 23, 2013 at 8:12 PM, Fujii Masao <masao(dot)fujii(at)gmail(dot)com> wrote:
> On Thu, Jan 24, 2013 at 8:47 AM, Phil Sorber <phil(at)omniti(dot)com> wrote:
>> On Wed, Jan 23, 2013 at 6:07 PM, Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us> wrote:
>>> Phil Sorber <phil(at)omniti(dot)com> writes:
>>>> On Wed, Jan 23, 2013 at 1:58 PM, Bruce Momjian <bruce(at)momjian(dot)us> wrote:
>>>>> On Wed, Jan 23, 2013 at 12:27:45PM -0500, Tom Lane wrote:
>>>>>> +1 for default timeout --- if this isn't like "ping" where you are
>>>>>> expecting to run indefinitely, I can't see that it's a good idea for it
>>>>>> to sit very long by default, in any circumstance.
>>>
>>>>> FYI, the pg_ctl -w (wait) default is 60 seconds:
>>>
>>>> Great. That is what I came to on my own as well. Figured that might be
>>>> a sticking point, but as there is precedent, I'm happy with it.
>>>
>>> I'm not sure that's a relevant precedent at all. What that number is
>>> is the time that pg_ctl will wait around for the postmaster to start or
>>> stop before reporting a problem --- and in either case, a significant
>>> delay (multiple seconds) is not surprising, because of crash-recovery
>>> work, shutdown checkpointing, etc. For pg_isready, you'd expect to get
>>> a response more or less instantly, wouldn't you? Personally, I'd decide
>>> that pg_isready is broken if it didn't give me an answer in a couple of
>>> seconds, much less a minute.
>>>
>>> What I had in mind was a default timeout of maybe 3 or 4 seconds...
>>
>> I was thinking that if it was in a script you wouldn't care if it was
>> 60 seconds. If it was at the command line you would ^C it much
>> earlier. I think the default linux TCP connection timeout is around 20
>> seconds. My feeling is everyone is going to have a differing opinion
>> on this, which is why I was hoping that some good precedent existed.
>> I'm fine with 3 or 4, whatever can be agreed upon.
>
> +1 with 3 or 4 secounds.
>
> Aside from this issue, I have one minor comment. ISTM you need to
> add the following line to the end of the help message. This line has
> been included in the help message of all the other client commands.
>
> Report bugs to <pgsql-bugs(at)postgresql(dot)org>.

Ok, I set the default timeout to 3 seconds, added the bugs email to
the help, and also added docs that I forgot last time.

Also, still hoping to get some feedback on my other issues.

Thanks.

>
> Regards,
>
> --
> Fujii Masao