This technique is great if you have no customers from countryX but are being targeted by a DoS, unwanted crawlers, bots, scrapers and other baddies. Please don’t use this to discriminate against less profitable countries. The web should be open for all. Thanks.
If you’re not already using Nginx, you should get it even if you already have a great web server. Put it in front and get it to act as a reverse proxy.
First grab this perl script which you …

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There has been some recent confusion about how much memory you need in a web server to handle a huge number of concurrent requests. I also made a performance claim on the STS list that got me an unusual number of private emails.
Here’s how you run a highly concurrent website on a shoe-string budget:
The first thing you’ll do is get a Linode server because they have the fastest CPU and disk.
Install Apache with your web application running under mod_php, mod_perl …

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It’s funny how when you’re troubleshooting a performance issue on your servers that suddenly made the load average spike to 14 (350% with four CPU cores) at 6:30am on a Sunday morning (yay!) all the stats look like garbage until you figure out what it is and then it’s so glaringly obvious that you spend the rest of the day kicking yourself for not seeing it immediately.
Note to self: Next time make coffee, drink coffee, and only then log on …

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Have you ever tried to get Apache to handle 10,000 concurrent connections? For example, you have a very busy website and you enable keepalive on your web server. Then you set the timeout to something high like 300 seconds for ridiculously slow clients (sounds crazy but I think that’s Apache’s default). All of a sudden when you run netstat it tells you that you have thousands of clients with established connections to your machine.
Apache can’t handle 10,000 connections efficiently because …

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