Forum Moderators: phranque
I'm doing some tests on Apache webserver (both 1.3 and 2.0 suffer from this problem) on Linux Debian 2.4 with enough CPU and enough RAM.
The load linear raises upto 8000 transactions/sec (this is 250 Mbps) and then suddenly falls down to 10 transactions/sec. At the time the server gets 8000 transactions/sec the CPU is almost 100% used (50% in kernel and 50% in user space), it then starts to spawn lots of child-processes and the CPU becomes idle!
It seems like there's no work done anymore, there are more than maxSpareServers not working, but they aren't cleaned up until the load disappears, no more requests and then one-by-one the child-processes are killed...
I don't get any logs that can help me out here.
Anyone familiar with this problem?
Thanks a lot in advance
Welcome to WebmasterWorld!
Since there haven't been any other replies, I'll hazard a guess that all available processes have been consumed, but are held as persistent connections, and won't drop until they time out. You might want to investigate the related settings and see if lowering the timeout helps.
Hopefully, someone who knows more about tuning busy servers will pop in with a more authoritative answer.
Jim
