On Fri, Jan 21, 2011 at 20:25, Mag Gam <magawake@xxxxxxxxx> wrote: > Typo, in Box 5. Wrong kernel version > > Box 5, RHEL 5.4, 2.6.36, dd bs=1024 count=1000000 if=/dev/zero > bs=4096k of=/dev/null > > Anyone had a chance to try this? :-) $ for a in `seq 1 3`; do \time dd bs=4K count=1M if=/dev/zero of=/dev/null; done 1048576+0 records in 1048576+0 records out 4294967296 bytes (4.3 GB) copied, 1.38893 seconds, 3.1 GB/s 0.21user 1.17system 0:01.39elapsed 99%CPU (0avgtext+0avgdata 2768maxresident)k 0inputs+0outputs (0major+209minor)pagefaults 0swaps 1048576+0 records in 1048576+0 records out 4294967296 bytes (4.3 GB) copied, 1.39358 seconds, 3.1 GB/s 0.23user 1.16system 0:01.39elapsed 99%CPU (0avgtext+0avgdata 2768maxresident)k 0inputs+0outputs (0major+209minor)pagefaults 0swaps 1048576+0 records in 1048576+0 records out 4294967296 bytes (4.3 GB) copied, 1.4527 seconds, 3.0 GB/s 0.17user 1.23system 0:01.45elapsed 96%CPU (0avgtext+0avgdata 2752maxresident)k 0inputs+0outputs (0major+208minor)pagefaults 0swaps I slightly modified your dd test. Again, this is on 2.6.36. IMO, you shouldn't worry much about it. Were experiencing something that related to memory access? It's not a NUMA box, right? Or are you using PAE? just capping into 896 MB maybe? non standart VM split other than 3:1? PS: I rewrite the subject to better match the discussion. With the hope readers well get better understanding about what the discussion is all about. Hope you don't mind.... -- regards, Mulyadi Santosa Freelance Linux trainer and consultant blog: the-hydra.blogspot.com training: mulyaditraining.blogspot.com _______________________________________________ Kernelnewbies mailing list Kernelnewbies@xxxxxxxxxxxxxxxxx http://lists.kernelnewbies.org/mailman/listinfo/kernelnewbies
