I have read through the notes in the default config file notes on the topic. Here's the notes from the file: > # TAG: cache_replacement_policy > # The cache replacement policy parameter determines which > # objects are evicted (replaced) when disk space is needed. > # > # lru : Squid's original list based LRU policy > # heap GDSF : Greedy-Dual Size Frequency > # heap LFUDA: Least Frequently Used with Dynamic Aging > # heap LRU : LRU policy implemented using a heap > # > # Applies to any cache_dir lines listed below this. > # > # The LRU policies keeps recently referenced objects. > # > # The heap GDSF policy optimizes object hit rate by keeping smaller > # popular objects in cache so it has a better chance of getting a > # hit. It achieves a lower byte hit rate than LFUDA though since > # it evicts larger (possibly popular) objects. > # > # The heap LFUDA policy keeps popular objects in cache regardless of > # their size and thus optimizes byte hit rate at the expense of > # hit rate since one large, popular object will prevent many > # smaller, slightly less popular objects from being cached. > # > # Both policies utilize a dynamic aging mechanism that prevents > # cache pollution that can otherwise occur with frequency-based > # replacement policies. > # > # NOTE: if using the LFUDA replacement policy you should increase > # the value of maximum_object_size above its default of 4096 KB to > # to maximize the potential byte hit rate improvement of LFUDA. > # > # For more information about the GDSF and LFUDA cache replacement > # policies see http://www.hpl.hp.com/techreports/1999/HPL-1999-69.html > # and http://fog.hpl.external.hp.com/techreports/98/HPL-98-173.html. > #Default: > # cache_replacement_policy lru I really don't understand the difference between: cache_replacement_policy lru & cache_replacement_policy heap LFUDA *Question 1* In the description above under heap LFUDA above, is it implying that the default lru setting somehow takes into account the size of the files as well? > . . . heap LFUDA policy keeps popular objects in cache regardless of their > size . . . . *Question 2* Does lru just dump the largest files first? As I am more interested in caching larger files, (like windows updates), and after reading this submission <http://squid-web-proxy-cache.1019090.n4.nabble.com/recommended-memory-cache-replacement-policy-tp1039362p1039368.html> I was thinking of using this setup: > cache_replacement_policy heap LFUDA > cache_dir ufs /var/spool/squid3_cache_1 51200 16 256 > cache_dir ufs /var/spool/squid3_cache_2 51200 16 256 > cache_dir ufs /var/spool/squid3_cache_3 51200 16 256 > cache_dir ufs /var/spool/squid3_cache_4 51200 16 256 > > memory_replacement_policy heap GSDF > maximum_object_size_in_memory 2048 KB *Question 3* Have I placed the replacement policy tags in the correct place - ie. above the cache_dir's and maximum_object_size_in_memory? Thanks for the assistance -- View this message in context: http://squid-web-proxy-cache.1019090.n4.nabble.com/cache-replacement-policy-Clarification-Please-Thank-You-tp4661855.html Sent from the Squid - Users mailing list archive at Nabble.com.
