RE: [squid-users] Multi ISP Load Balancing Problem

From: Lazuardi Nasution <mrxlazuardin@dont-contact.us>
Date: Wed, 5 Mar 2008 01:58:45 +0700

Hi,

I'm using Windows 2000 with Service Pack 4. If you think that it is a file
descriptor problem, why this problem apear when I install 3 Squid Services
but not happen on previous configuration which install one Squid Service
only ? I don't understand about select(). The Loop related error has been
solved by not using ICP between Main to both Parent and Parent to Parent
sibling relation ship. But the performance with 3 Squid Services still bad.

Best regards,

-----Original Message-----
From: Guido Serassio [mailto:guido.serassio@acmeconsulting.it]
Sent: Monday, March 03, 2008 12:37 AM
To: Lazuardi Nasution; squid-users@squid-cache.org
Subject: RE: [squid-users] Multi ISP Load Balancing Problem

Hi,

At 19:51 28/02/2008, Lazuardi Nasution wrote:
>We are using Squid 2.6STABLE18 for Windows. The performance is so bad.
>Here is some of weird things on log file, I don't have any idea of them.

Exactly what Windows version ? I hope that you are using a Windows Server
2003 machine ....

>2008/02/28 11:17:38| comm_select: select failure: (10038) WSAENOTSOCK,
>Socket operation on nonsocket.
>2008/02/28 11:17:38| Select loop Error. Retry 10
>FATAL: Select Loop failed!
>Squid Cache (Version 2.6.STABLE18): Terminated abnormally.
>CPU Usage: 106.922 seconds = 35.922 user + 71.000 sys Maximum Resident
>Size: 41444 KB Page faults with physical i/o: 12269
>
>These errors only happen when there is many users are accessing the Squid.
>These errors didb't happen when I just using one instance and do load
>balancing by separating tcp_outgoing_address on Squid Main based on odd
>or even clients source address, I'm not satisfied with this load
>balancing method.

Don't forget that scalability of Squid on Windows is very limited:
- Maximum file descriptors number is hard coded to 2048 in the Microsoft C
Runtime library, so you can safely support a top of around 660 CONCURRENT
object requests without user authentication.
Please note: OBJECT requests, not concurrent USERS.
- For portability reasons, the comm loop is based on select(), this is not
the better thing for speed.

Here you can find some tips on tuning TCP on Windows:
http://smallvoid.com/article/winnt-tcpip-max-limit.html

Regards

Guido

-
========================================================
Guido Serassio
Acme Consulting S.r.l. - Microsoft Certified Partner
Via Lucia Savarino, 1 10098 - Rivoli (TO) - ITALY
Tel. : +39.011.9530135 Fax. : +39.011.9781115
Email: guido.serassio@acmeconsulting.it
WWW: http://www.acmeconsulting.it/
Received on Tue Mar 04 2008 - 12:00:03 MST

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