[squid-users] Urgent Help Needed: Any suggestion on CPU utiliztion increased from 73% to 97.5 after cache_mem increased from 4 GB to 8 GB

Hey , guys,

Recently I did some interesting performance testing .

I used memory only for the squid configuration . when I set the the
cache_mem to following value , I got incresed CPU utilization .

cache_mem 4096 MB, cpu :73% (the value from top or squidclient mgr:info)
cache_mem 6144 MB , cpu : 85 %
cache_mem 8192 MB , cpu : 97.5%

I am really wondering why CPU utiliztion get such increse ....

I used the same traffic load for the testing .

Following is my testing configuration .
1. Hardware configuration
 (1) Squid Server
CPU: 2 AMD 64 bits 2.4GHz CPUs, eachCPU has 2 Cores
 Memory size: 16G,
 (2) Client and Web Server : Web Polygraph 3.1.5

 2. Squid version
:squid-2.6.STABLE19<http://www.squid-cache.org/Versions/v2/2.6/squid-2.6.STABLE19-RELEASENOTES.html>

Configuration:
./configure --enable-dlmalloc ...etc...

one Squid instance is running on the cache server ,
 squid .conf :
cache_mem 8192 MB
maximum_object_size_in_memory 2048 KB
memory_replacement_policy heap GDSF
cache_dir null /tmp
memory_pools on
memory_pools_limit 256 MB

Best Regards
-Arkin
Received on Sat Jun 14 2008 - 06:10:49 MDT