Note: "permalinks" may not be as permanent as we would like,
direct links of old sources may well be a few messages off.
You're probably FSB bound. Without DRBD you're probably doing direct DMA transfers that don't affect your FSB. You need to split the memory and I/O traffic so they're not on the same bus. You'd do better with a CPU that has an integrated memory controller and separate I/O channels. The performance you're seeing isn't bad for your hardware. -JR On Mon, Jan 31, 2011 at 6:11 PM, Mark Petersen <mpetersen at peak6.com> wrote: > Hi, > > > > I’m trying to use DRBD with the backend storage on a FusionIO device (NAND > Flash without disk controller overhead.) I’ve found that I’m taking a huge > performance hit via testing with fio. > > > > IOPS > > `fio --directory=/fio/test --direct=1 --rw=randread --bs=4k --size=5G > --numjobs=64 --runtime=10 --group_reporting --name=file1` > > raw device: 104k > > drbd device: 75k > > > > Bandwidth > > `fio --directory=/fio/test --direct=1 --rw=randread --bs=1m --size=5G > --numjobs=4 --runtime=100 --group_reporting --name=file1` > > raw device: 750 MB/s > > drbd device: 550-600 MB/s > > > > I’ve tried drbd 8.3.9 and 8.3.10 and while 8.3.10 might be slightly better, > it’s mostly insignificant (1-2%.) > > > > The backend for writing is 2 x 1GB bonded round robin dedicated interfaces, > but since I’m seeing a read hit I’m not concerned with this potential write > bottle neck at the moment unless it’s somehow related, I plan to use 10 gig > cards in the near future if this works out. > > > > ? The DRBD process seems be CPU bound, but performance is worse if I > change cpu affinity to be more than 1 core. This is on a E5430 @ 2.66GHz. > I imagine a faster CPU could improve performance, but I’m looking for other > suggestions of course. > > Other Relevant Details: > > CentOS 5.5 > > Kernel 2.6.18-194 > > Filesystem XFS > > drbd 8.3.9 and 8.3.10 compiled into rpm’s from source (any compile time > tweaks I could use, such as CPU type?) > > > > Thanks, > > Mark > ------------------------------ > See http://www.peak6.com/email_disclaimer.php for terms and conditions > related to this email > > _______________________________________________ > drbd-user mailing list > drbd-user at lists.linbit.com > http://lists.linbit.com/mailman/listinfo/drbd-user > > -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://lists.linbit.com/pipermail/drbd-user/attachments/20110202/eee3bccc/attachment.htm>