Measure of rolling hash

$ make clean ; make
rm -rf o
mkdir o
cc -O3 -c -o o/main.o sources/main.cpp
cc -O3 -c -o o/ZRollingHash.o sources/ZRollingHash.cpp
cc -O3 -lc++ -o bin/rate o/main.o o/ZRollingHash.o
bin/rate
sizeof char: 1 unsigned: 4 long: 8 char*: 8
Prime buffer (256 MB)...
     405 (ms) - prime buffer
Prime rolling hash 1...
Scan buffer for at least 30 seconds...
   29562 (ms) - passes:    171 chunks:  11628 total:    45902462976 average:  3947580 rate:   1480 MB/s

$ make
bin/rate
sizeof char: 1 unsigned: 4 long: 8 char*: 8
Prime buffer (256 MB)...
     389 (ms) - prime buffer
Prime rolling hash 1...
Scan buffer for at least 30 seconds...
   29384 (ms) - passes:    170 chunks:  11560 total:    45634027520 average:  3947580 rate:   1481 MB/s