It's of course not mem speed measure as mentioned before in the forum :-) It's RAID - spped measure. stupid fault. raid5: measuring checksumming speed 8regs : 77961.200 MB/sec 8regs_prefetch: 56.400 MB/sec 32regs : 94.800 MB/sec 32regs_prefetch: 95.200 MB/sec raid5: using function: 8regs (77961.200 MB/sec) But anyway, it's strange. Perhaps only a missing division /1000.