Stability. Give it credit for being - probably - the most widely used implementation of malloc in the world. I say this as someone who has implemented a lock-f

Stability. Give it credit for being - probably - the most widely used implementation of malloc in the world. I say this as someone who has implemented a lock-free memory allocator for mutlithreaded applications. I cared about performance, and I was willing to sacrifice nice things like detecting double-frees. I moved away from the project largely because I didn't want to be in a performance race with TCMalloc. (At the end, TCMalloc outperformed my allocator in some benchmarks, but not in others. But, surprisingly, there were also some places were glibc outperformed both.)