sometimes sluggish performance

Hi.

After a few weeks of trying to solve this problem and reading the FAQ, i'm
still nowhere to solving it :( The situation is as follows:

I run Squid 2.2-STABLE3 (tried STABLE2 also) on a 486DX4-100 with 52 MB
running Mandrake 6.0 with a 2.3.x kernel. The reason why I run 2.3.x is
because of the updated isdn-drivers. But I also tried with a 2.2.x kernel,
but that didn't matter. The first few minutes Squid performs as expected,
but after 15 minutes or so, it becomes partially sluggish. By partially I
mean that if a requested object is available from the cache then that
object is served as fast as possible, but if it needs to get it from the
internet (parent proxy or no parent proxy) then the speed drops
dramatically and it stalls all the time. I know it isn't a bandwidth
problem, because if i don't use the proxy, I have full bandwidth. But then
maybe 10 minutes later, i have full bandwidth again using Squid.

I also played with the cache_mem setting. Setting it higher or lower than
the default 8 MB had no effect. The cache size is 100 MB with 8 1st level
subdirs and 16 2nd level subdirs. But one thing struck me as odd. The
following is a partial output of the cachemgr.cgi program:

Connection information for squid:
        Number of clients accessing cache: 3
        Number of HTTP requests received: 262
        Number of ICP messages received: 40
        Number of ICP messages sent: 40
        Number of queued ICP replies: 0
        Request failure ratio: 0.00%
        HTTP requests per minute: 4.3
        ICP messages per minute: 1.3
        Select loop called: 15155 times, 240.593 ms avg
Cache information for squid:
        Request Hit Ratios: 5min: 68.6%, 60min: 80.8%
        Byte Hit Ratios: 5min: 53.9%, 60min: 44.9%
        Storage Swap size: 19650 KB
        Storage Mem size: 136 KB
        Storage LRU Expiration Age: 365.00 days
        Mean Object Size: 8.78 KB
        Requests given to unlinkd: 11
Median Service Times (seconds) 5 min 60 min:
        HTTP Requests (All): 0.03427 0.03829
        Cache Misses: 0.06640 1.71839
        Cache Hits: 0.03427 0.03427
        Near Hits: 0.00000 1.11539
        Not-Modified Replies: 0.00000 0.00000
        DNS Lookups: 0.00000 0.04639
        ICP Queries: 0.00000 0.00000
Resource usage for squid:
        UP Time: 3646.184 seconds
        CPU Time: 12.880 seconds
        CPU Usage: 0.35%
        CPU Usage, 5 minute avg: 0.34%
        CPU Usage, 60 minute avg: 0.35%
        Maximum Resident Size: 0 KB
        Page faults with physical i/o: 378
Memory usage for squid via mallinfo():
        Total space in arena: 2748 KB
        Ordinary blocks: 2718 KB 35 blks
        Small blocks: 0 KB 0 blks
        Holding blocks: 176 KB 1 blks
        Free Small blocks: 0 KB
        Free Ordinary blocks: 29 KB
        Total in use: 2894 KB 105%
        Total free: 29 KB 1%
Memory accounted for:
        Total accounted: 653 KB
File descriptor usage for squid:
        Maximum number of file descriptors: 1024
        Largest file desc currently in use: 39
        Number of file desc currently in use: 20
        Files queued for open: 0
        Available number of file descriptors: 1004
        Reserved number of file descriptors: 100
        Store Disk files open: 0
Internal Data Structures:
          2242 StoreEntries
            31 StoreEntries with MemObjects
            29 Hot Object Cache Items
          2239 Filemap bits set
          2239 on-disk objects

Notice in the Squid Resource Usage section that the 'Maximum Resident Size'
equals 0. Does that mean that squid has no limitation in memory usage? Is
my problem known to other users and if so, is there a solution to this?
Please, help me with this problem, because it's driving me nuts :((

If you need some additional info, just let me know.

Grtz Gerben.
Received on Tue Jun 22 1999 - 09:11:36 MDT