Uploaded February 2023 | Updated September 2026, 3 weeks ago

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Thanks to Omer from Egypt for submitting this question: github.com/mariocynicys/mem-hog
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Making our own executable packer: fasterthanli.me/series/making-our-own-executable-packer

Contents
00:00 What does the program do?
04:35 Memory usage, Vec, and jemalloc
06:18 How does malloc even work?
07:22 Visualizing allocations with memusage
11:14 Where is the heap? /proc/PID/maps
14:24 Virtual memory vs RSS
16:00 Tracing syscalls with strace
19:50 Virtual memory vs physical memory
20:50 The madvise syscall
22:31 What's technique 2 doing?
23:37 Iterator size hints
24:56 What's technique 3 doing?
30:31 Mystery solved
34:53 Thanks & outro