Apache 2.4 vs Nginx Benchmark Showdown

Disclaimer: This test was highly unscientific, with a +/- 10% fabricated margin of error.  No maths were performed to gather proper averages and statistics.  No effort was made to ensure consistency of the two Apache builds and no legitimate effort was made with regard to proper scientific rigor during this test.  This test does not take into account memory usage, responsiveness of the server under load, or any other relevant metric that would be of more use than this test.  I highly encourage you to do your own testing and draw your own conclusions.

How the tests were performed: 
I wanted to simulate a VPS environment similar to a basic Linode.  A base install of Ubuntu Server 10.04 was installed in VMWare with an older/slower 7200RPM sata drive for storage.  This drive was not in use by any other system during the test, nor were any other VMs active on the host.  The guest was given 512MB of RAM and 1 CPU core of the host's 8 cores.  The host's CPUs are dual Xeon X5365 @ 3Ghz.

Apache 2.2 was installed along with nginx 0.7.65, later Apache 2.4 was compiled on this same system.

Testing was performed using Apache JMeter on an 8 core Xeon workstation running Windows 7 and 32GB of RAM  with a 1Gb/s link to the VMWare host.  Requests per second were determined by rounding off the throughput displayed in the Summary Report listener.  Each test was run until the requests per second stabilized.

The Apache 2.2 server was only tested with the Prefork MPM, while the Apache 2.4 server was tested with both Prefork and Event.  Apache's KeepAlive setting was on throughout the testing and set at 2 seconds.

Update:
I received several requests to post memory usage statistics so I've updated the Jquery test with memory results.  Again, care was not taken to keep the Apache builds consistent.  It concerns me that the Prefork build of Apache 2.4 was using so much memory compared to the other Apache builds.  Take these results with a grain of salt, but trust that Nginx definitely uses significantly less memory than Apache.

Update 2 - Nginx 1.0.12:
I received some flak for using an older version of Nginx, so I tested with Nginx 1.0.12 and it was around 4% slower than the results shown here.

Test 1 - 21KB text file

HTTP Server	Req/s
Apache 2.2 Prefork	2220
Apache 2.4 Prefork	2250
Apache 2.4 Event	2300
Nginx	2600

Test 2 - 2B text file consisting of a single period.

HTTP Server	Req/s
Apache 2.2 Prefork	4400
Apache 2.4 Prefork	4700
Apache 2.4 Event	4810
Nginx	6650

Test 3 - jquery.min.js (92KB)

HTTP Server	Req/s	Memory Usage
Apache 2.2 Prefork	650	12MB
Apache 2.4 Prefork	770	72MB
Apache 2.4 Event	820	20MB
Nginx	1000	2MB

Test 4 - PHP output of phpinfo()

HTTP Server	Req/s
Apache 2.2 Prefork	525
Apache 2.4 Prefork	575
Nginx FastCGI	450