eng.age

Riding the Riptide

The Problem

Normally when we talk about traffic at a CDN, we think about pushing data out to customers. While this seems like it should just involve straightforward transmissions, it turns out things can be a bit more complex.

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Malloc Lives In Userspace (and why you care)

Python, Ruby and Java handle memory management for us. Containerization and “serverless” operation let us do more and more on a single server, and work at ever higher levels of abstraction. But they don’t actually make the server underneath go away and the nitty gritty details of kernels, memory allocation, and storage can still ruin your day. Learn a few lessons about memory based on experiences running a CDN at a scale large enough to serve Tbps of traffic.

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So you think you can core?

    Segmentation fault (core dumped)

Bad luck: Your software just crashed. It happens to all of us, and when it does Linux will write a core dump file with some information about what was happening in the address space of the program when it crashed. If you are feeling a little adventurous, you can do some fun and interesting things with exactly how and where those cores get dumped.

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