[squid-users] squid performance tunning

I have some Dell 1950 servers dedicated to squid in my production
environment. Each with 16GB RAM and 300G disk
As the website traffic grows, the load of squid becomes high at high
traffic time. Average load is higher than 10.

Device: rrqm/s wrqm/s r/s w/s rkB/s wkB/s avgrq-sz
avgqu-sz await svctm %util
sda 0.00 0.01 0.06 0.13 1.23 1.45 28.87
    0.00 4.13 2.19 0.04
sda1 0.00 0.01 0.06 0.11 1.23 1.45 31.59
    0.00 4.52 2.40 0.04
sdb 0.07 0.07 0.01 0.01 0.33 0.32 59.88
    0.00 19.75 15.74 0.03
sdc 0.00 2.08 9.13 104.44 81.30 1066.74
20.22 0.50 11.95 1.73 19.63

avg-cpu: %user %nice %system %iowait %steal %idle
           3.50 0.00 3.75 24.34 0.00 68.41

Device: rrqm/s wrqm/s r/s w/s rkB/s wkB/s avgrq-sz
avgqu-sz await svctm %util
sda 0.00 0.00 0.50 0.00 2.00 0.00 8.00
    0.04 70.00 70.00 3.50
sda1 0.00 0.00 0.50 0.00 2.00 0.00 8.00
    0.04 70.00 70.00 3.50
sdb 0.00 0.00 0.00 0.00 0.00 0.00 0.00
    0.00 0.00 0.00 0.00
sdc 0.00 0.00 21.50 186.00 204.00 3106.25
31.91 17.76 100.55 2.63 54.65

Here is the squidclient mgr:info output

Squid Object Cache: Version 3.1.12
Start Time: Sun, 14 Aug 2011 19:39:15 GMT
Current Time: Thu, 18 Aug 2011 04:41:20 GMT
Connection information for squid:
        Number of clients accessing cache: 77651
        Number of HTTP requests received: 40449309
        Number of ICP messages received: 0
        Number of ICP messages sent: 0
        Number of queued ICP replies: 0
        Number of HTCP messages received: 0
        Number of HTCP messages sent: 0
        Request failure ratio: 0.00
        Average HTTP requests per minute since start: 8319.3
        Average ICP messages per minute since start: 0.0
        Select loop called: 476454933 times, 0.612 ms avg
Cache information for squid:
        Hits as % of all requests: 5min: 30.7%, 60min: 32.1%
        Hits as % of bytes sent: 5min: 40.5%, 60min: 43.2%
        Memory hits as % of hit requests: 5min: 88.3%, 60min: 88.8%
        Disk hits as % of hit requests: 5min: 1.6%, 60min: 1.9%
        Storage Swap size: 120792244 KB
        Storage Swap capacity: 90.0% used, 10.0% free
        Storage Mem size: 5191632 KB
        Storage Mem capacity: 100.0% used, 0.0% free
        Mean Object Size: 20.61 KB
        Requests given to unlinkd: 0
Median Service Times (seconds) 5 min 60 min:
        HTTP Requests (All): 0.00865 0.00865
        Cache Misses: 0.01035 0.01035
        Cache Hits: 0.00000 0.00000
        Near Hits: 0.00091 0.00091
        Not-Modified Replies: 0.00000 0.00000
        DNS Lookups: 0.00000 0.00000
        ICP Queries: 0.00000 0.00000
Resource usage for squid:
        UP Time: 291725.519 seconds
        CPU Time: 37204.391 seconds
        CPU Usage: 12.75%
        CPU Usage, 5 minute avg: 19.42%
        CPU Usage, 60 minute avg: 18.20%
        Process Data Segment Size via sbrk(): 1012440 KB
        Maximum Resident Size: 28552368 KB
        Page faults with physical i/o: 2957
Memory usage for squid via mallinfo():
        Total space in arena: -1265560 KB
        Ordinary blocks: -1308538 KB 264611 blks
        Small blocks: 0 KB 0 blks
        Holding blocks: 20708 KB 9 blks
        Free Small blocks: 0 KB
        Free Ordinary blocks: 42978 KB
        Total in use: -1287830 KB 103%
        Total free: 42978 KB -3%
        Total size: -1244852 KB
Memory accounted for:
        Total accounted: -1781767 KB 143%
        memPool accounted: 6606841 KB -531%
        memPool unaccounted: -7851693 KB 0%
        memPoolAlloc calls: 10008474163
        memPoolFree calls: 10065124847
File descriptor usage for squid:
        Maximum number of file descriptors: 20480
        Largest file desc currently in use: 4828
        Number of file desc currently in use: 4703
        Files queued for open: 178
        Available number of file descriptors: 15599
        Reserved number of file descriptors: 100
        Store Disk files open: 22
Internal Data Structures:
        5860834 StoreEntries
        256880 StoreEntries with MemObjects
        256646 Hot Object Cache Items
        5860661 on-disk objects

related parameters

cache_mem 5120 MB
maximum_object_size 51200 KB
maximum_object_size_in_memory 1024 KB

log_icp_queries off
cache_swap_low 90
cache_swap_high 95
hosts_file /etc/squid/hosts
cache_dir aufs /export/squid/cache 131072 32 256

Is there any idea I can tune my squid performance?
Received on Thu Aug 18 2011 - 06:19:22 MDT