[squid-users] heavy load server's performance

Hi,all:

    Our squid box's performance is not very good(40000 reqs/min), cpu
load is very high, and the traffic can't great bigger than
100MBits/s.(Gbits/s network).

    We use aufs scheme now.We have a test for coss, and the result is
not very good also(cpu overload also).

    can we optimize continue?Is the best performace that our hardware
can achived?where is the bottle-neck?

    what is the best performance of your box?

there are some infomations:

++++++ hardware:
    cpu: Xeon 1.8G(Hyper-Threading)
    os: RHAS 4.3
    file discriptor num: 32768
    mem: 2G
    disk: OS: 17G(scsi) for OS,
            cache:73G(SCSI,10000rpm for cache data)

++++++ squid.conf
    about 100 ACLs
    cache_mem 1500 MB
    cache_dir coss /dev/sdb1 50000 max-size=10000000 block-size=8192
    (some server use aufs: cache_dir aufs /cache/cache 50000 240 256,
and sdb1 is mounted with options of async and noatime)

++++++ top:
top - 11:37:46 up 42 days, 12:00, 1 user, load average: 1.00, 0.99, 0.91
Tasks: 54 total, 3 running, 51 sleeping, 0 stopped, 0 zombie
Cpu(s): 41.8% us, 8.3% sy, 0.0% ni, 47.9% id, 1.3% wa, 0.7% hi, 0.0% si
Mem: 2074980k total, 1979160k used, 95820k free, 686568k buffers
Swap: 4192956k total, 3404k used, 4189552k free, 355632k cached

  PID USER PR NI VIRT RES SHR S %CPU %MEM TIME+ COMMAND
 3738 squid 25 0 918m 714m 2104 R 99.9 35.3 63:59.56 squid
 3901 root 16 0 3664 912 740 R 0.3 0.0 0:00.04 top
    1 root 16 0 3312 236 208 S 0.0 0.0 0:04.01 init

++++++ mgr:info

Squid Object Cache: Version 2.6.STABLE12
Start Time: Thu, 22 Mar 2007 02:34:09 GMT
Current Time: Thu, 22 Mar 2007 03:21:32 GMT
Connection information for squid:
        Number of clients accessing cache: 9967
        Number of HTTP requests received: 1705959
        Number of ICP messages received: 0
        Number of ICP messages sent: 0
        Number of queued ICP replies: 0
        Request failure ratio: 0.00
        Average HTTP requests per minute since start: 36012.7
        Average ICP messages per minute since start: 0.0
        Select loop called: 1805771 times, 1.574 ms avg
Cache information for squid:
        Request Hit Ratios: 5min: 97.9%, 60min: 97.6%
        Byte Hit Ratios: 5min: 83.9%, 60min: 78.7%
        Request Memory Hit Ratios: 5min: 9.6%, 60min: 18.2%
        Request Disk Hit Ratios: 5min: 16.3%, 60min: 7.5%
        Storage Swap size: 240512 KB
        Storage Mem size: 241140 KB
        Mean Object Size: 26.95 KB
        Requests given to unlinkd: 0
Median Service Times (seconds) 5 min 60 min:
        HTTP Requests (All): 0.00919 0.00562
        Cache Misses: 0.09736 0.10281
        Cache Hits: 0.00919 0.00562
        Near Hits: 0.06640 0.05331
        Not-Modified Replies: 0.00865 0.00463
        DNS Lookups: 0.03868 0.06364
        ICP Queries: 0.00000 0.00000
Resource usage for squid:
        UP Time: 2842.262 seconds
        CPU Time: 2911.327 seconds
        CPU Usage: 102.43%
        CPU Usage, 5 minute avg: 87.11%
        CPU Usage, 60 minute avg: 102.57%
        Process Data Segment Size via sbrk(): 378764 KB
        Maximum Resident Size: 0 KB
        Page faults with physical i/o: 0
Memory usage for squid via mallinfo():
        Total space in arena: 378764 KB
        Ordinary blocks: 297942 KB 10127 blks
        Small blocks: 0 KB 0 blks
        Holding blocks: 401944 KB 6 blks
        Free Small blocks: 0 KB
        Free Ordinary blocks: 80821 KB
        Total in use: 699886 KB 90%
        Total free: 80821 KB 10%
        Total size: 780708 KB
Memory accounted for:
        Total accounted: 552999 KB
        memPoolAlloc calls: 147261049
        memPoolFree calls: 147041272
File descriptor usage for squid:
        Maximum number of file descriptors: 32768
        Largest file desc currently in use: 6319
        Number of file desc currently in use: 5784
        Files queued for open: 0
        Available number of file descriptors: 26984
        Reserved number of file descriptors: 100
        Store Disk files open: 0
        IO loop method: epoll
Internal Data Structures:
          8976 StoreEntries
          4571 StoreEntries with MemObjects
          4537 Hot Object Cache Items
          8924 on-disk objects

-- 
Best regards
Felix New