Re: [COMMITTERS] pgsql: Add TCP keepalive support to libpq.

On Jun 24, 2010, at 16:30 , Robert Haas wrote:
> On Thu, Jun 24, 2010 at 10:13 AM, Tom Lane <tgl@sss.pgh.pa.us> wrote:
>> Simon Riggs <simon@2ndQuadrant.com> writes:
>>> On Wed, 2010-06-23 at 21:54 +0000, Robert Haas wrote:
>>>> This adds four additional connection parameters to libpq: keepalives,
>>>> keepalives_idle, keepalives_count, and keepalives_interval.
>>>> keepalives default to on, per discussion, but can be turned off by
>>>> specifying keepalives=0.  The remaining parameters, where supported,
>>>> can be used to adjust how often keepalives are sent and how many
>>>> can be lost before the connection is broken.
>>
>>> There isn't any need at at all for this. We can already add options on
>>> the libpq connection line.
>>
>>> options = '-o tcp_keepalives_idle=X
>>> tcp_keepalives_interval=Y
>>> tcp_keepalives_count=Z'
>>
>> Huh?  The above is 100% fanciful; there was no code in libpq or anywhere
>> else that would have processed such a thing.
>
> You can do this:
>
> psql "host=127.0.0.1 options='-c tcp_keepalives_idle=1'"

Hm, seems a bit error-prone though. The difference between the above

psql "host=127.0.0.1 keepalives=1"

isn't immediately obvious I'd say.

Should we maybe rename the libpq-side parameters to tcp_client_keepalives, tcp_client_keepalives_idle,
tcp_client_keepalives_countand tcp_client_keepalives_interval? Or do we expect people who fiddle with those parameters
tounderstand the subtle difference? 

best regards,
Florian Pflug