Dear All, I have recently set up a Squid cache using WCCP and a cisco router. I am getting very impressive performance for my cache hits, but my cache misses sometimes take as long as 4 seconds! We are at the end of a high bandwidth, high latency satellite link with a normal latency (for example: to google.com) of around 600ms round-trip. So why the 4 second delay? Sometimes it comes down to 1.3sec but even that is a lot slower than I would expect when my cache hits are being pumped out in 0.017s Any ideas? Here's my cachemanager stats (I've marked the relevant line with an asterisk) : Squid Object Cache: Version 2.5.STABLE9 Start Time: Thu, 15 Jun 2006 08:43:36 GMT Current Time: Fri, 16 Jun 2006 07:14:09 GMT Connection information for squid: Number of clients accessing cache: 46 Number of HTTP requests received: 556986 Number of ICP messages received: 0 Number of ICP messages sent: 540 Number of queued ICP replies: 0 Request failure ratio: 0.00 Average HTTP requests per minute since start: 412.4 Average ICP messages per minute since start: 0.4 Select loop called: 12369540 times, 6.551 ms avg Cache information for squid: Request Hit Ratios: 5min: 33.2%, 60min: 30.2% Byte Hit Ratios: 5min: 10.9%, 60min: 16.3% Request Memory Hit Ratios: 5min: 6.2%, 60min: 8.9% Request Disk Hit Ratios: 5min: 28.7%, 60min: 27.1% Storage Swap size: 19916692 KB Storage Mem size: 102392 KB Mean Object Size: 13.80 KB Requests given to unlinkd: 0 Median Service Times (seconds) 5 min 60 min: HTTP Requests (All): 1.62803 1.71839 ** Cache Misses: 3.11263 2.79397 Cache Hits: 0.01745 0.01745 Near Hits: 1.38447 1.24267 Not-Modified Replies: 0.01164 0.01164 DNS Lookups: 0.01535 0.02033 ICP Queries: 0.00000 0.00000 Resource usage for squid: UP Time: 81033.414 seconds CPU Time: 2825.424 seconds CPU Usage: 3.49% CPU Usage, 5 minute avg: 8.78% CPU Usage, 60 minute avg: 8.15% Process Data Segment Size via sbrk(): 283308 KB Maximum Resident Size: 0 KB Page faults with physical i/o: 3 Memory usage for squid via mallinfo(): Total space in arena: 283308 KB Ordinary blocks: 282627 KB 36898 blks Small blocks: 0 KB 0 blks Holding blocks: 11528 KB 6 blks Free Small blocks: 0 KB Free Ordinary blocks: 680 KB Total in use: 294155 KB 100% Total free: 680 KB 0% Total size: 294836 KB Memory accounted for: Total accounted: 215351 KB memPoolAlloc calls: 79976881 memPoolFree calls: 76613850 File descriptor usage for squid: Maximum number of file descriptors: 4096 Largest file desc currently in use: 571 Number of file desc currently in use: 433 Files queued for open: 0 Available number of file descriptors: 3663 Reserved number of file descriptors: 100 Store Disk files open: 0 Internal Data Structures: 1446719 StoreEntries 20863 StoreEntries with MemObjects 20747 Hot Object Cache Items 1443710 on-disk objects Regards, Ben Hathaway
