Slow Response Sun ONE 6.1 SP3 Win 2003

Question

My Sun ONE web server is processing my JSP pages very quickly when serving one session at a time. However when there are 4 or more active sessions, it slows right down. Response time goes from 2 seconds (1 active session) to 60 seconds (multiple active sessions) for a single JSP page. I've been running the performance monitor to see if I can notice anything, but nothing seems to stand out. I have tried manipulating the Keep Alive settings and the Performance settings within the Magnus Editor but there hasn't been a noticable improvement.
I've recently upgraded to SP4 to see if this solved my problem, but there was no imporvement.
This server is an HP DL380 with dual 2.8GHz Xeon processors & 2 Gigs of RAM. There is a lot of available disk space. I'm running Windows 2003 and it's up to date with all the latest patches.
Anyone have any ideas or experienced this before?
I've attached the output from my performance monitor:
webservd pid: 4280
Sun ONE Web Server 6.1SP4 B01/20/2005 21:34 (WINNT DOMESTIC)
Server started Thu Mar 03 09:41:06 2005
Process 4280 started Thu Mar 03 09:41:06 2005
ConnectionQueue:
Current/Peak/Limit Queue Length 0/1/4096
Total Connections Queued 126
Average Queue Length (1, 5, 15 minutes) 0.00, 0.00, 0.00
Average Queueing Delay 0.02 milliseconds
ListenSocket ls1:
Address http://10.178.132.7:8080
Acceptor Threads 8
Default Virtual Server https-guruweb01
KeepAliveInfo:
KeepAliveCount 2/64
KeepAliveHits 1083
KeepAliveFlushes 0
KeepAliveRefusals 0
KeepAliveTimeouts 11
KeepAliveTimeout 360 seconds
SessionCreationInfo:
Active Sessions 2
Keep-Alive Sessions 1
Total Sessions Created 48/256
CacheInfo:
enabled yes
CacheEntries 110/1024
Hit Ratio 1912/2164 ( 88.35%)
Maximum Age 30
Native pools:
NativePool:
Idle/Peak/Limit 5/6/128
Work Queue Length/Peak/Limit 0/1/0
Server DNS cache disabled
Async DNS disabled
Performance Counters:
Average Total Percent
Total number of requests: 1213
Request processing time: 1.5520 1882.5520
default-bucket (Default bucket)
Number of Requests: 1213 (100.00%)
Number of Invocations: 15085 (100.00%)
Latency: 0.0002 0.2013 ( 0.01%)
Function Processing Time: 1.5518 1882.3507 ( 99.99%)
Total Response Time: 1.5520 1882.5520 (100.00%)
Sessions:
Process Status Function
4280 keep-alive
response service-dump
response service-j2ee
Thanks...

Answer 1

The JSP's are simply Hello World JSP's (however I created these type of JSP's for testing and they do respond slowly as well when these are multiple sessions).
These JSP functioned fine on iPlanet 6.0 SP1 (JDK 1.2.2) without any slow response on Win2K and inferior hardware.