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Date: Wed, 21 Mar 2001 19:44:03 -0500 (EST)
From: Stanislav Rost <prgrssor@cs.bu.edu>
To: new-httpd@apache.org, current-testers@apache.org
Subject: Behavior Under Linux, Benchmarking Curves and Cry for Help
Message-ID: <Pine.SOL.4.20.0103211943270.8778-100000@csb.bu.edu>
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Dear Apache developers,

I had been conducting high-stress experiments involving Apache on the
latest Linux 2.2.x kernels, in order to produce the usual "decline in
throughput and growth in latency with load" graphs for my research
paper.  To my dismay, I was unable to produce such graphs due to weird
behavior under high loads.  Namely, the benchmarking program that I was
using (BU's own SURGE) would frequently report a "Connection reset" error
during higher-load test runs (oftentimes upon a call to read(), so after 
the connection establishment), totally decimating any chance for obtaining
clean data points for the [majority of] test runs.  The Apache error log
produces no entries corresponding to such resets.

I was hoping some of the Apache developers may know the reason/fix to this
problem.

A little about the setup:  two P2-400's stressing another P2-400 with
>400-500 concurrent ongoing downloads of large files  
at any given instant of time (so high concurrency levels are
implicit).  Apache is directed to create at least that many threads on
startup.

My other question is for anyone who has ever successfully
benchmarked Apache under Linux and produced nice-looking graphs:  what
system and web server parameters did you tweak to obtain
high-stress results?  What was your setup?

Thank you very much, your responses are appreciated.

Stan Rost