Yes well good luck with that, i know it's a lot more dificult to work with async processes then sync like this one.
Meanwhile i successfully added the X-Accel-Redirect to my web server and php and it works great.. we will see how it behaves in the future where hopefully i will have thousands of users downloading their files
I have setup a LVS cluster in anycase , so i will use different servers for downloading.. so the performance won't affect me very much as i will increase the numbers of servers if the % of processor usage comes down to a max.
Is there any other way to measure the webserver usage??

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