Here's three things I wish I had read about Apache optimization that are not commonly discussed (we found out by years of trial and error). These three settings are worth more than all the other optimization we've done (e.g. SendBufferSize, AcceptFilter http data, EnableMMAP On, EnableSendfile On, eliminating all .htaccess files, etc.) 1. Set your KeepAliveTimeout to 3 seconds or less. 2. Turn off atime "accesss time" by using noatime. Do it in real time with *something like* the command line below. This will make it so you only have to read the file off the disk instead of doing both a read (to get the data) then a write to update the access time. shell> mount -o noatime,remount,rw / To make the noatime setting last between reboots edit your fstab and modify this line: /dev/VolGroup00/LogVol00 / ext3 defaults 1 1 To read *something like* to like this: /dev/VolGroup00/LogVol00 / ext3 defaults,noatime 1 1 3. Increase your StartServers to the number of maximum requests on your biggest page. For example, if your busiest page requires 30 hits/requests to load all the images, css, javascript, etc then if you have the RAM to support it, set your StartServers to 30 and your MinSpareServers to 30. To know if you have the RAM to support it, run the command "top" and look for the httpd process under the column "RES." That's the amount of physical RAM the Apache process is taking up. On our server, each process take up about 12 megs of RAM. So having 30 Apache process running will takes up 360 megs of RAM. Now use Firefox Firebug. Look at the time each item is in "waiting." Before you increased StartServers you might see the first 10 or 20 items have a "waiting" time of 20 to 30 ms then the last 10 items have a "waiting" time of 300 or 500ms or more. When you have enough processes going, all the "waiting" times will be about the same. Don't raise your StartServers above the amount of RAM available otherwise you'll swap which I've read is very slow (you can tell by looking at the "top" output under the row called "swap"). Money and premature optimization is the root of all evil. Best, http://www.t1shopper.com/ -+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ "The nine most terrifying words in the English language are: I'm from the government and I'm here to help." - Ronald Reagan, August 21, 1986 -+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
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