On Sun, Feb 15, 2004 at 01:05:25PM +0100, Keld Jørn Simonsen wrote: > On Sun, Feb 15, 2004 at 01:54:11AM -0800, Matt Thrailkill wrote: > > The you don't get as good performance because hdc1 is slow enough to > > really drag it down. Think about it, if reads are all going about > > sequentially, it has to spend alot of time waiting on that 16mb/s drive > > compared to the others. > > I would have thought the disks would have worked towards gaining > performance enhancements in some cumulative way, is that not so, in theory? > > So why is 3 disks slower than 2? > > > You probably can't get 100mb/s with the two because that would be pretty > > efficient, and there's probably more overhead than that. > > > > Shouldn't the 80gb drive be going faster than 16mb/s though? Have you > > checked hdparm to make sure dma and all the goodies are turned on for > > it? > > I have a 40 GB segate disk also, on the same motherboard IDE > controller, it runs about 40 MB/s. So yes, the hdc1 > should go faster, and I have measured something like 40 MB/s > on it in idler times. I think it is because it is running other > processes. The machine is a ftp mirror and the disk has RedHat > and Fedora ISO images, so it is quite popular. Hmm, I have ext3 filesystems, and they are updating the atime in the inodes. Could that be it? inode flushing obstructing the striping? Best regards Keld - To unsubscribe from this list: send the line "unsubscribe linux-raid" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
