Hello, Need some guidance for optimal sharing of cache amongst SMP workers using Large rock. Context: I am using squid cache with 8 SMP workers and a 200 GB rock cache stored on SMP. (Using squid-3.HEAD-20140127-r13248 which has LargeRock support to cache objects > 32 KB). I have set : maximum_object_size 4 MB cache_dir rock /mnt/squid-cache 204800 max-size=4194304 cache_mem 0 MB My refresh pattern is very permissive which basically allows caching everything: refresh_pattern . 129600 100% 129600 ignore-auth Questions: I am trying to test optimal caching behavior where after I have downloaded 1 GB data (~16000 objects ~64KB each) the subsequent download should all be cache hits. However, I see several TCP misses in access.log. The hit ratio on subsequent download of the same objects is ~85%. 1. Is this expected in a multiple worker setup? If yes, can you please briefly explain what contributes towards these misses and how can this be minimized? 2. I set cache_mem to 0 coz I believe cache_mem sharing is opportunistic and hence all workers might not always share all objects in cache_mem. Is that correct? What impact does cache_mem size have on deterministic sharing of cache between workers. 3. Moreover are there any tips/guidelines to optimize % hit rate for previously downloaded objects. Thanks, Rajiv
