Here's an update on my experience with moving some web apps into mod_perl:

stricting everything pretty much worked for me. I don't seem to have any strange variable problems. Oh, and I saw an eight-fold (798%) increase in performance. Oof!

They requests I tested do a couple of select queries and one update to a "pageaccess" table, and output a page and graphic of about 5k. Admittedly small, but that's how I keep pages anyway.

I did these tests loopback, so no bandwidth restrictions apply here. Look at the "Requests per second" value. Here's the skinny, from ApacheBench:

Not using mod_perl

Concurrency Level:      50
Time taken for tests:   87.313 seconds
Complete requests:      1000
Failed requests:        0
Total transferred:      5232000 bytes
HTML transferred:       5085000 bytes
Requests per second:    11.45
Transfer rate:          59.92 kb/s received
[download]

Same test, using mod_perl

Concurrency Level:      50
Time taken for tests:   10.943 seconds
Complete requests:      1000
Failed requests:        0
Total transferred:      5232000 bytes
HTML transferred:       5085000 bytes
Requests per second:    91.38
Transfer rate:          478.11 kb/s received
[download]

Same box, static page

Concurrency Level:      50
Time taken for tests:   0.754 seconds
Complete requests:      1000
Failed requests:        0
Total transferred:      4510800 bytes
HTML transferred:       4243680 bytes
Requests per second:    1326.26
Transfer rate:          5982.49 kb/s received
[download]

As expected, dynamic pages are far slower than static. But the acceleration afforded by mod_perl has brought the per-second page value for dynamic pages above the limit imposed by my bandwidth (1.5 megabit T1, which works out to around 55 pages a second in my testing.) That means it'll be hard to choke my server with mod_perl accelerated dynamic pages. My bandwidth will be used up long before I overtax my disk and processor speed.

Server stats, for those interested:

• IBM Netfinity 4000 (I think that's the model #)
• dual PIII 550 mhz procs
• 512 meg ECC ram
• 4 gig SCSI for OS and user files
• 4 gig SCSI for swap and extra space
• 2x4 gig SCSI mirrored RAID for web files
• RH 6.2 with patches
• Using NuSphere for Apache, mySQL and mod_perl

My next project is setting up persistent mySQL connections to squeeze even more speed out of this puppy