Demos

The programs demonstrated during the lecture, one directory per part of it.

Each demo is small on purpose: it makes one point, and it is meant to be run rather than read. The write-up in each directory says what to expect, what actually happens, and why.

Demo	Part of the lecture	What it shows
00-pitch/	00. Pitch	Memory runs out, speeds things up, slows things down, and leaks.
02-memory-operations/	02. Memory operations	Allocate, read, write, execute, free -- and which of those fault.
03-address-space/	03. The process address space	The list of areas of a process, static and dynamic, under pmap.
04-allocation-time/	04. When memory is allocated	Where each kind of variable lands, and which were placed by the linker.
05-runtime-allocation/	05. Run-time allocation	The stack, the heap and mappings growing and shrinking; malloc() turning into brk() or mmap().

Part 01 has no demo; its two measurements are in the pitch.

Running them

Every demo that needs building has a Makefile, so make inside its directory is enough. The tools the demos need, beyond a C compiler and make, are:

• pmap (procps), to print the address space of a running process
• strace, to see the system calls malloc() makes
• valgrind, for the leak in 00-pitch/memory-leak
• perf (linux-tools), to count cache misses in 00-pitch/cache-memory -- needs sudo
• gdb, readelf, size, nm (binutils), for looking inside executables and faults

Several demos wait at prompts so that pmap can be run on them from a second terminal; they are marked as such in their READMEs. utils/utils.h holds the DIE() macro the sources share.