Theoretical connections/second limit using Varnish

Poul-Henning Kamp phk at
Fri May 1 12:44:42 CEST 2009

In message <49FACE30.7010309 at>, Nick Loman writes:

>I'm sure I could find a way of getting Apache to put in a 10msec 
>Keep-Alive timeout if that was necessary.
>Are you proposing that Varnish would then hold and re-use that backend 
>connection for a waiting request from a different user/TCP connection?

Varnish tries as hard as reasonable to reuse both client and backend

If your appache gives varnish just a short chance to do so, I am
sure that you can eliminate 40-50% of your connections.

>> If you run a tcpdump of the backend traffic, does the connections
>> close properly with FIN or does one of the ends RST them ?

OK, just making sure.

Poul-Henning Kamp       | UNIX since Zilog Zeus 3.20
phk at FreeBSD.ORG         | TCP/IP since RFC 956
FreeBSD committer       | BSD since 4.3-tahoe    
Never attribute to malice what can adequately be explained by incompetence.

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