RE: Round robin parents get the same URL

Thanks to Duane WESSELS 's reply, I think I understand what happens.
It is mainly related to the Integralis Websweeper non ICP parents.
The websweepers do a lot of content analysis stuff which can be very slow. So
they periodically generate so-called "conforting messages" which are basically
HTML pages telling the users to kindly wait.
But the very last conforting message is not really a conforting message but
rather the initial URL requested by the user. And then the user is supposed to
 receive all the requested document very quickly (direct transfer between the
Websweeper and the browser).
But this last conforting message is seen as regular URL by the Squid, so the
parent is round robin selected; And if this parent is not the same as the
parent selected during the real user request, all the websweeper stuff must be
 done again.

The HTTP 302 is generated by the Websweepers.
And the 3 minutes delay is the time needed by a Websweeper to analyze the
content of the nsps35.tar.gz file.

So what I think would be great would be a URL hashing algorithm to select the
parent. This way, the same URL request would be always forwarded to the same
Websweeper.

Any comments?

Emmanuel.

-----Original Message-----
From: Duane Wessels [mailto:wessels@nlanr.net]
Sent: Wednesday, May 27, 1998 8:33 PM
To: ADELINE E InfoEmiAsp
Cc: 'squid'
Subject: Re: Round robin parents get the same URL

ADELINE E InfoEmiAsp writes:

>Ok for the definition of "round robin".
>But from an user point of view, there has been only one request.
>Fromy previous example, I entered only once the URL http:
>//squidexterne/test/nsps35.tar.gz
>But in the access log file, the URL appeared twice!!!
>And worse, the 2 parents (non-ICP, but UDP echo) did the same work almost in
 
>parallel.
>
>Therefore, I think I missed something very big in the config file !!!! But
>what?

>>Here is a new excerpt from the access.log:
>>
>>896267803.153 3648 192.32.86.29 TCP_MISS/302 84 GET http:
>>//squidexterne/test/nsps35.tar.gz X007178 FIRST_PARENT_MISS/pcnt -
>>896267976.495 3830 192.32.86.29 TCP_MISS/302 85 GET http:
>>//squidexterne/test/nsps35.tar.gz X007178 FIRST_PARENT_MISS/pcnt2 -

Your client must be making the same request twice. These two
accesses are separated by almost three minutes in time.

Also note the HTTP reply is 302 (Moved Temporarily). These
replies are not cached.

Duane W.
Received on Thu May 28 1998 - 02:50:28 MDT