W3C home > Mailing lists > Public > public-qa-dev@w3.org > October 2003

Re: [checklink] very long checking times - any idea?

From: Ville Skyttä <ville.skytta@iki.fi>
Date: Thu, 09 Oct 2003 21:24:53 +0300
To: Olivier Thereaux <ot@w3.org>
Cc: public-qa-dev@w3.org
Message-Id: <1065723893.11132.100.camel@bobcat.mine.nu>

On Thu, 2003-10-09 at 19:46, Olivier Thereaux wrote:

> I just got reports of "sluggishness" for checklink. I checked, and it 
> seems indeed like checklink takes > 5 seconds to HEAD each resource.
[...]
>
> Ville, do you have any idea what could cause this, or any experience of 
> similar trouble?

At least there are some DNS problems on v.w.o.  The primary nameserver
(ie the first one in /etc/resolv.conf) doesn't answer at all, others
seem to be fine.  The effect can be witnessed eg. by running the
following several times and comparing the results:

   time HEAD -d http://www.w3.org/
   time HEAD -d http://18.29.1.34/

A 5 second DNS timeout somewhere?  I was about to suggest running nscd
on v.w.o but it seems to be running named anyway...

There are some problems with checklink that prevent HTTP Keep-Alive
working too well, the LWP::UserAgent instances aren't always reused. 
That may cause the delay even between requests to the same hostname
during a single checklink run.
Received on Thursday, 9 October 2003 14:24:55 GMT

This archive was generated by hypermail 2.2.0+W3C-0.50 : Thursday, 19 August 2010 18:12:43 GMT