Stephen Sanders wrote: > I'm trying a disk throughput experiment where in two 3ware raid 6's are > being put into a g_strip raid 0. > > The raid 6's are using 8 7200RPM disks. The disk transfer rate is > ~80MB/s. Using a load generation tool that is using O_DIRECT for I/O, > I've generated the following short output from iostat. Needless to say, > the write performance is a lot less than I'm expecting. > > We've modified the kernel such that our KB/t figure is closer to 512KB/t > per disk when measured without the g_strip. With g_strip turned on, the > KB/t number is more like 60KB/t. > > The question is how do I get g_stripe to write larger transactions to > the disk ?
How old is your system? There was bug, fixed 8-12 months ago, making fast mode in gstripe not working on systems with increased MAXPHYS. As I understand, it is what you've changed in your kernel. -- Alexander Motin _______________________________________________ freebsd-performance@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-performance To unsubscribe, send any mail to "freebsd-performance-unsubscr...@freebsd.org"
