Re: Apache::Clean worthwhile in addition to mod_gzip ?

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Hi Jonathan,

On Thu, 2005-02-24 at 11:13, Jonathan Vanasco wrote:

> a _ what is the typical overhead in terms of cpu use -- ie, 
> cpu/connection time saved by smaller/faster downloads vs those used by 
> zipping

The short answer is: The typical CPU overhead originated from the
content compression is insignificant.

Actually, in my observations over the files up to 200K it was estimated
as less then 60 ms on P4 3 GHz processor. I could not measure the low
boundary reliably. I can suggest to count some 10 ms per request on
"regular" web pages for estimation of performance, but I would refrain
from betting on this recommendation really.

The estimation of a connection time is even more complicated, because of
a variety of possible features on the network. The worse scenario is
pretty impressive: Slow dial-up user connected via the ISP with no
proxy/buffering holds your socket for a while that is proportional to
the size of the requested file. So far, gzip can make this some 3-20
times shorter. However, if the ISP is buffered, you might be feeling not
that bad apart of the fact that you are paying to your X-Telecom for the
transmission of a "blank data".

> b_ just to clarify, mod_deflate is the only chain usable for apache 2 
> -- and the various Apache:: perlmods are unneeded are incompatible?

Basically, this is true for the Apache::Dynagzip at least, and I was
thinking that this is stated pretty clear in FAQ. Additional tiny
filters could be prepended to mod_deflate on Apache-2 in order to make
necessary features when required.

Thanks,
Slava
--
http://www.lastmileisp.com/