Memory issues

[Cleber de Melo]

I am stress testing an web application (ASP) hosted on an Windows 2300 Server Standard Edition
SP1, installed on a dual processor (x86 Family 15 Model 5 Stepping 10 AuthenticAMD 2193 Mhz).

According to winmsd command, total physical memory is equal to 4.030 MB and total virtual memory
is 1,78GB. This is a little bit weird as it should be 2GB, according to docs I´ve read about
Windows virtual memory.

But more strange is the fact that when I submit a heavy load to the Web Server (IIS and ASP Server)
the memory available doesn´t change significantly. I used both winmsd command and the
performance monitor. There is also no significant increase in swapping, cpu or disk usage. The only
think we see is an increase in ASP request queue.

I show below some numbers got from performance monitor execution (interval of 5 seconds).

Anyone has some clue what is going on?

Thanks.

Cleber




Time/PM counters ASP

executing | queued | reqs/sec

Before 9 | 2 | 15
During 42 | 152 | 25


ASP - Sessions Current

Before 914
During 2188



Memory

MB Available| Pages/sec

Before 3374 | 3
During 3389 | 3


Memory

Output/sec | Trans. Faults/sec

Before 0 | 882
During 0 | 976


Memory - Commited Bytes
Before 450465792
During 479277875



Physical Disk (Total)

% Disk Time | Disk Queue Length

Before 10 | 1
During 9 | 1


Processor(Total)
% Processor Time | % User Time
Before 46 | 41
During 70 | 63




Paging File (Total)
% Usage
Before 2
During 1


System / Processor Queue Length
Before 3
During 6



Process(Total) / Working Set

Before 395902976
During 422690816


Web Service(my site)
Anonymous Users | Connections

Before 12 | 929
During 180 | 1046

[Rune J. Winje]

Virtual memory will be whatever your pagefile.sys is configured to be... or maybe usage of it.

Disk usage and queue looks nice.

CPU load increases, 6 in cpu queue is not so good...

Theory: Primarily your test produces network traffic where the CPU is used for that. Can probably be improved by new network cards/drivers that support cpu offloading (the NIC does more of the computation, while the cpu gets a rest)


Cheers,
Rune

[Cleber de Melo]

Rune,

Thank you for your comments.

My pagefile.sys is set as custom size from 2GB to 4GB. So I can´t underestand why the Total Virtual Memory is set to only 1.78GB.

According to you, the bottleneck rests in networking. But I cannot see why the ASP Server experienced an extreme queueing acitivity as seen in my test.

Intuitivily, I would expect all computer resources measures reaching a low level watermark and the user perceiving a huge response time due to the network bottleneck.

In fact, both the response time and throughput are bad in my testes, but I thought the reason was the queueing in ASP Server.

Finally, the more weird in the measures was the "memory available". It remained almost
stationary in 3GB before and during the test execution. It´s something I´ve never expected
in a heavy load condition.

Thank you once more for your remarks.

Best Regards.

Cleber