Thursday, September 30, 2010

Linux Kernel Tuning for C500k | Urban Airship Blog

By Jared "Lucky" Kuolt on September 29, 2010

Like the idea of working on large scale problems? We’re hiring talented engineers, and would love to chat with you – check it out!


Note: Concurrency, as defined in this article, is the same as it is for The C10k problem: concurrent clients (or sockets).

At Urban Airship we recently published a blog post about scaling beyond 500,000 concurrent socket connections. Hitting these numbers was not a trivial exercise so we’re going to share what we’ve come across during our testing. This guide is specific to Linux and has some information related to Amazon EC2, but it is not EC2-centric. These principles should apply to just about any Linux platform.

For our usage, squeezing out as many possible socket connections per server is valuable. Instead of running 100 servers with 10,000 connections each, we’d rather run 2 servers with 500,000 connections apiece. To do this we made the socket servers pretty much just socket servers. Any communication between the client and server is passed through a queue and processed by a worker. Having less for the socket server to do means less code, cpu-usage, and ram-usage.

Friday, September 3, 2010

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