Re: [PATCH] dnscache: merge similar outgoing udp packets

On Thu, Apr 16, 2009 at 05:26:40PM -0500, Mark Johnson wrote:

> > This patch is only lightly tested. Use on production servers at your own
> > risk (and please report to the list if you have success using it).
> 
> This will be going into the much delayed zinq-djbdns-0.06.

Thanks. The list has been silent on success reports, so perhaps nobody
is actually using it. I've been running it for a few weeks now without
incident, but only on a lightly loaded server (and only on dnscache --
the changes shouldn't affect other programs, but I haven't tested it
extensively).

> Recommended value for MERGEQUERIES?  Obviously dnscache doesn't care,
> but envdir will not set an environment variable if the corresponding
> file is empty.  I'd be tempted to just use '1' or 'ON' except that
> suggests you can turn query merging off by setting it to '0' or 'OFF',
> when what they really have to do is remove the file or truncate it to
> zero bytes.  Is there a best practice?  I do intend to modify
> dnscache-conf to create a MERGEQUERIES file in the env directory so
> that query merging is on by default in zinq-djbdns.

I would just use "1", which I see you did in the new zinc release. I
agree that the "0 still enables" behavior is confusing and has bitten
people on the list, but I think it is better to be consistent with the
existing options (which is why I implemented it as I did).

-Peff