Apache2 slow serving static while healthy
- by user45339
My Apache status looks like;
201 requests/sec - 98.8 kB/second - 504 B/request
85 requests currently being processed, 345 idle workers
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Server load is average 2 on a 4 core machine.
IO utilization is 10-15% and doesn't have many jumps over 70%.
Machine has almost 4 gb free and uses 0 swap.
The site on the machine is a PHP site. All PHP code is optimized and fast mostly when it gets accessed, however sometimes requests get stuck. Stuck meaning; no response for at least 10 sec. We debugged the PHP code, but it is quite optimal and fast. We spend a lot of time on it until we decided to test the requesting of:
<html><body>test</body></html>
test.html page.
This static resource also gets 'stuck' in the same manner the php pages get 'stuck'.
How is the possible given the health of the system?
I tested the network, but, when the PHP shows 'slowness' in the site monitoring, the html test files also take (far longer) than 10 sec to load using;
time lynx -dump http://127.0.0.1/test.html
We are kind of desperate to solve this problem, but we cannot seem to tackle it.
