My cached objects will expire after 10 minutes.
Cache-Control:max-age=600
I don't know why there are so many disk writes and there are so many
objects on disk.
In addtion, Disk hits as % of hit requests: 5min: 1.6%, 60min: 1.9%
is very low.
Can I increase the cache_mem？ or not use disk cache at all?
2011/8/18 Łukasz Makowski <lukasz.makowski_at_itsoft.pl>:
> W dniu 2011-08-18 08:19, Chen Bangzhong pisze:
>>
>> 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?
>>
> Hi,
>
> First of all, I would try to change cache_dir acces method from aufs to
> diskd and experiment with Q1 and Q2 parameters.
>
> Regards,
>
> LM
>
>
Received on Thu Aug 18 2011 - 06:53:20 MDT
This archive was generated by hypermail 2.2.0 : Thu Aug 18 2011 - 12:00:04 MDT