Re: keepalives on MacOS X

Fujii Masao <masao.fujii@gmail.com>

From: Fujii Masao <masao.fujii@gmail.com>
To: Robert Haas <robertmhaas@gmail.com>
Cc: Tom Lane <tgl@sss.pgh.pa.us>, pgsql-hackers@postgresql.org
Date: 2010-06-30T02:53:33Z
Lists: pgsql-hackers
On Tue, Jun 29, 2010 at 11:28 PM, Robert Haas <robertmhaas@gmail.com> wrote:
> On Tue, Jun 29, 2010 at 12:42 AM, Tom Lane <tgl@sss.pgh.pa.us> wrote:
>> Yeah, a bit of rooting around in the Darwin sources shows that this
>> value is used as a per-connection override for tcp_keepidle.  So it
>> is a synonym.  Not sure if it's worth supporting when the other value
>> can't be set too.  Maybe it'd be more useful to document that people can
>> set the system-wide values if they're desperate.
>
> Well, the default value for tcp_keepidle is 2 hours, and the default
> value for tcp_keepintvl is 75 seconds.  Assuming that tcp_keepcount
> defaults to something reasonable (I think the default on Linux is 9),
> the lion's share of the time will be waiting for tcp_keepidle - so
> just the ability to reduce that value to something reasonable should
> help a lot.  It's also not much code - proposed patch attached.

src/interfaces/libpq/fe-connect.c
+		appendPQExpBuffer(&conn->errorMessage,
+						  libpq_gettext("setsockopt(TCP_KEEPIDLE) failed: %s\n"),
+						  SOCK_STRERROR(SOCK_ERRNO, sebuf, sizeof(sebuf)));

s/TCP_KEEPIDLE/TCP_KEEPALIVE

Don't we need to change pq_getkeepalivesidle?

In pq_setkeepalivesidle, if neither TCP_KEEPIDLE nor TCP_KEEPALIVE are
supported, the following message is output.

    setsockopt(TCP_KEEPIDLE) not supported

We should change it to something like?

    neither setsockopt(TCP_KEEPIDLE) nor setsockopt(TCP_KEEPALIVE) are supported

Regards,

-- 
Fujii Masao
NIPPON TELEGRAPH AND TELEPHONE CORPORATION
NTT Open Source Software Center