anyone using tracking gifs?

handling lots of gif downloads

[bb22]

Hello,
I have a small site hosted on a dedicated server (small as well 1.7ghz/ide) and offering besides its main content limited traffic stats. Those stats are collected for sites that include a small gif tracker (hosted on my site) on their pages. A cron job parses my server logs and generates the stats. My site itself is not demanding at all in terms of resources.
So far so good, but call me a victim of my success, many sites with *lots* of visitors have included the trackers on their site. I don't have performance problems yet but foresee them coming if the flow of sites using them keeps coming.
Bandwidth and CPU don't worry me too much, i am more watching number of processes (currently above 300 any time), of tcp connections (around 600), and of apache slots used (and of course server load).

So here are the questions:
- the apache max clients defaults (100) on my server were quickly reached, so i have set the maxclients to 300 and lowered the keepalivetimeout down to 10 secs (was 15). Was this a good move? What are potentialy bad implications of changing those two parameters?
- is there generally a hard limit for max number of tcp connections / processes, and how can i get an estimation of it (this is more a linux question but well).
- My mrtg shows network/hd interrupts, HD R/W IO and ctxt/processes graphs, how do i interpret them to avoid incoming problems (this is more linux as well, a pointer to a *good* tutorial about mrtg/monitoring would be nice, couldn't find any...)
- what suggestions would you have for tuning an apache server in such a context?

All suggestions are very welcome, i'm a beginner to this so don't think any comment could be "too basic".

thanks!

[jdMorgan]

Does anyone have any suggestions to offer to bb22?

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