Experiments ought to be repeatable. Here is a quick bash/perl script to generate the parts he left out. It expects that you have copied his main module to a f

Experiments ought to be repeatable. Here is a quick bash/perl script to generate the parts he left out. It expects that you have copied his main module to a file called main.c in the CWD. echo "Generating funcs.h" perl -e 'for ($i=0;$i<=1000000;$i++) {print "int f${i}(void);\n";}' > funcs.h echo "Generating funcs.c" perl -e 'print "#include \"funcs.h\"\n\n";for ($i=0;$i<=1000000;$i++) {print "int f${i}() {return ".($i+1)."; }\n";}' > funcs.c echo "Generating tab.h" perl -e 'print "#include \"funcs.h\"\n\n";print "int (*func_table[])(void) = {\n";for ($i = 0; $i <= 1000000; $i++) {print "f${i},\n";}print "};\n";' > tab.h echo "Compiling funcs.c" time gcc -O0 -c -o funcs.o funcs.c echo "Compiling main.c" time gcc -O0 -c main.c -o main.o echo "Linking..." time gcc -O0 main.o funcs.o -o func-time echo "Running..." time ./func-time I'm using gcc 4.x which seems to generate a slightly smaller function (10 bytes vs. 11): 00000000 <f0>: 0: 55 push %ebp 1: 89 e5 mov %esp,%ebp 3: b8 01 00 00 00 mov $0x1,%eax 8: 5d pop %ebp 9: c3 ret I ran it on a 3GHz Xeon with 4MB cache (so 2MB per core I think) and I get roughly the same, but with much reduced compile times. Running... code size: 10 time: 30 secs code size: 100 time: 48 secs code size: 1000 time: 49 secs code size: 10000 time: 47 secs code size: 100000 time: 51 secs code size: 1000000 time: 59 secs code size: 10000000 time: 202 secs