I am using 2.6STABLE3 on kernel 2.6.8-2 After a couple of hours Squid took all mem available. What is causing this ? I had the same problem when using 2.5. Mem: 906752k total, 902464k used, 4288k free, 32168k buffers Swap: 3911816k total, 4k used, 3911812k free, 637096k cached PID USER PR NI VIRT RES SHR S %CPU %MEM TIME+ COMMAND 2781 proxy 15 0 174m 168m 2616 S 1.0 19.0 1:31.55 squid This is my squid.conf: http_port 3128 transparent cache_mem 128 MB cache_swap_low 90 cache_swap_high 95 maximum_object_size 15000 KB minimum_object_size 0 KB maximum_object_size_in_memory 128 KB cache_replacement_policy heap GDSF memory_replacement_policy heap GDSF cache_dir aufs /harddisk/squid/cache 20000 47 256 memory_pools off client_persistent_connections off server_persistent_connections off pipeline_prefetch off