Hi: I am running squid version 3.3.8 on CentOS v6.5. I have an issue regarding file descriptors. Our proxy has run into an issue the past few days (everyone streaming FIFA soccer I believe) where we receive the following error: WARNING! Your cache is running out of filedescriptors At this point the CPU usage of each squid worker spikes to 100% and the SNMP agent becomes unavailable. I was able to get some information from squidclient mgr:info. My question is around the file descriptor statistics: When the issue is happening it reports: File descriptor usage for squid: Maximum number of file descriptors: 16384 Largest file desc currently in use: 548 Number of file desc currently in use: 540 Files queued for open: 0 Available number of file descriptors: 15844 Reserved number of file descriptors: 100 Store Disk files open: 0 After a restart of squid it reports the following: File descriptor usage for squid: Maximum number of file descriptors: 65536 Largest file desc currently in use: 516 Number of file desc currently in use: 475 Files queued for open: 0 Available number of file descriptors: 65061 Reserved number of file descriptors: 400 Store Disk files open: 0 The ulimit setting for the OS is 8192 for open files. According to the documentation for max_filedescriptors (which I don't have set in my squid.conf) the default value is the ulimit value. Therefore why on first startup does it list the max FD of 65k? Also, when the issue arises why does it end up dropping to 16k? According to the output above there is at any point roughly only 1k FD in use, so why is squid reporting that it is running out of FD? Any assistance would be appreciated. Thanks