Hi, I don't know how to handle memory for squid. Squid automatically breaks down itself and restarts: In my squid.conf I set: url_rewrite_children 120 startup=30 idle=100 concurrency=0 max_filedesc 7168 cache_swap_low 60 cache_swap_high 80 I notice that just one pending requests queued: 2011/06/09 11:00:17| WARNING: All redirector processes are busy. 2011/06/09 11:00:17| WARNING: 1 pending requests queued and follow is more details of cache.log: 2011/06/09 11:00:16| WARNING: Cannot run '/opt/squid-3.1.10/urlrewriter_new.pl' process. 2011/06/09 11:00:16| ipcCreate: fork: (12) Cannot allocate memory 2011/06/09 11:00:16| WARNING: Cannot run '/opt/squid-3.1.10/urlrewriter_new.pl' process. 2011/06/09 11:00:16| ipcCreate: fork: (12) Cannot allocate memory 2011/06/09 11:00:16| WARNING: Cannot run '/opt/squid-3.1.10/urlrewriter_new.pl' process. 2011/06/09 11:00:16| ipcCreate: fork: (12) Cannot allocate memory 2011/06/09 11:00:16| WARNING: Cannot run '/opt/squid-3.1.10/urlrewriter_new.pl' process. 2011/06/09 11:00:17| WARNING: All redirector processes are busy. 2011/06/09 11:00:17| WARNING: 1 pending requests queued 2011/06/09 11:00:17| storeDirWriteCleanLogs: Starting... 2011/06/09 11:00:17| WARNING: Closing open FD 177 2011/06/09 11:00:17| Finished. Wrote 16367 entries. 2011/06/09 11:00:17| Took 0.01 seconds (1308941.14 entries/sec). FATAL: Too many queued redirector requests Squid Cache (Version 3.1.10): Terminated abnormally. <---------------------------------- CRASH *** CPU Usage: 6631.678 seconds = 4839.266 user + 1792.412 sys Maximum Resident Size: 0 KB Page faults with physical i/o: 3299 Memory usage for squid via mallinfo(): total space in arena: -1160028 KB Ordinary blocks: -1289701 KB 53024 blks Small blocks: 0 KB 1 blks Holding blocks: 15976 KB 6 blks Free Small blocks: 0 KB Free Ordinary blocks: 129672 KB Total in use: -1273725 KB 110% Total free: 129672 KB -10% 2011/06/09 11:00:26| Starting Squid Cache version 3.1.10 for x86_64-unknown-linux-gnu... 2011/06/09 11:00:26| Process ID 31241 2011/06/09 11:00:26| With 7168 file descriptors available