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pdpiyesterday at 9:15 PM1 replyview on HN

> A lot of the memory problems that you can see without a GC are hard to find and diagnose

The nastiest leak I've ever seen in a C++ production system happened inside the allocator. We had a really hostile allocation pattern that forced the book-keeping structures inside the allocator to grow over time.


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cogman10yesterday at 9:39 PM

To be fair, I've seen something similar with the JVM, though it recovers. G1GC when it was first introduced would create these massive bookkeeping structures in order to run collections. We are talking about off JVM heap memory allocations up to 20% of the JVM heap allocation.

It's since gotten a lot better with JVM updates, so much so that it's not a problem in Java 21 and 25.