Web Caching

Examples

The following is a fictitious CARP membership table that shows the global information section followed by the list of array members. The three array members should each appear on one line. These lines are too long to fit on the page, so they are wrapped around and indented:

Proxy Array Information/1.0
ArrayEnabled: 1
ConfigID: 12345
ArrayName: My-Array
ListTTL: 3600

proxy1.isp.net 10.2.3.4 3128 http://proxy.isp.net/carp.txt
    SmartCache-v1 21600 UP 1 2048
proxy2.isp.net 10.2.3.5 3128 http://proxy.isp.net/carp.txt
    SmartCache-v1 20127 UP 1 2048
proxy3.isp.net 10.2.3.6 3128 http://proxy.isp.net/carp.txt
    SmartCache-v1 22928 UP 1 2048

The following tables may be useful to developers who want to verify their implementation. Table C-1 is a list of proxy names and load factors. I took the program described previously and added printf statements to print the hash values, RLF, and LFM.

Table C-1. Proxy Array Values

Hostname	Hash Value	Load Factor	RLF	LFM
test1.ircache.net	0x96010320	1	0.142857	0.869442
test2.web-cache.com	0x84965f0f	1	0.142857	0.869442
test3.squid-cache.org	0x4f5d7332	2	0.285714	1.064844
test4.packet-pushers.com	0xa79af670	3	0.428571	1.242318

Table C-2 consists of hash values and Table C-3 shows CARP scores for five different URIs. The four scores correspond to the four proxy names given earlier. The score values are truncated (not rounded) after the decimal point to improve the readability of this table.

Table C-2. URI Hash Values

URI	Hash Value
http://www.squid-cache.org	0x16073a01
http://www.ircache.net ...