I find it mildly amusing that the author spends the first half of the article mocking squid for handling disk cache manually when varnish just hands the work to the OS instead, and then the second half of the article explaining how and why varnish does all its own memory management for processing requests instead of just letting the OS handle it.
No, the first half explains why varnish lets the OS manage virtual memory, then explains why varnish doesn't rely on the user space memory allocator that comes with the language. Two completely different layers and different things.
