Neil Brown wrote: > On Saturday November 26, djani22@xxxxxxxxxxxxx wrote: > > > > The cat /dev/nb# >/dev/null makes ~ 350 Mbit/s on each nodes. Why is this so slow? Or is this the max node-HD throughput? What's the node HW config? > > The cat /dev/nb0 + nb1 + nb2 + nb3 in one time parallel makes ~ 780-800 > > Mbit/s. - i think this is my network bottleneck. How much do you get w/ nb0+1,2,3 and nb0+1+2,3 respectively? > > But the cat /dev/md31 >/dev/null (RAID0, the sum of 4 nodes) only makes > > ~450-490 Mbit/s, and i dont know why.... > > > > Somebody have an idea? :-) > > Try increasing the read-ahead setting on /dev/md31 using 'blockdev'. > network block devices are likely to have latency issues and would > benefit from large read-ahead. Also try larger chunk-size ~4mb. -- Al - To unsubscribe from this list: send the line "unsubscribe linux-raid" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
