Hey Nathan. Since the Coraid devices are networked via ethernet, you could have several cabinets attached to one server if that's what you need.
Each virtual machine could have it's down RAID set exclusively for it's own use, with the right number of spindles to service its purpose. This works wonders by eliminating seek contention between VMs. Many people setup Xen with local disks mounted in the Dom0 as RAID, then use loopback files attached to the VM. As Ezra mentioned, at Engine Yard, we attached the Coraid block storage directly to the VM itself, and this is more efficient than loopback files. On Mar 27, 8:57 pm, "[EMAIL PROTECTED]" <[EMAIL PROTECTED]> wrote: > > What exactly are you trying to do? Do you need a clusteredfilesystem > > or just a bunch more disk IO per server? > > Yes, just a bunch more IO per virtual server. > > > The best bang for your buck > > as far as getting a ton of disk spindles is coraid san's using AoE. > > >http://coraid.com/pdfs/datasheets/EtherDriveSR2461.pdf > > That looks good. I am wondering where my IO bottleneck is exactly. > Is it in the number of spindles or the bus from the drives to the > motherboard. Would there be an advantage to using the coraid > etherdrive to host 24 sata disks over getting two beefy servers with > 12 drives each on a raid controller? > > For instance, I am currently running a physical server that is > transferring 40mbps - 60mbps of data evenly over about 40 xen virtual > machines. It is set up with only 4 large SATA drives. IOwait percent > is often over 50% on the domU's, cpu and other metrics are fine. > Obviously overloaded. Am I thinking correctly that I can solve this > problem for my next 50 vps's with 12 smaller SATA drives.. maybe 32 > instead of 8meg caches on the drives? Or is there still a huge > advantage to putting the drives on AoE? > > Thanks for your thoughts on this. > > -=nathan --~--~---------~--~----~------------~-------~--~----~ You received this message because you are subscribed to the Google Groups "Deploying Rails" group. To post to this group, send email to [email protected] To unsubscribe from this group, send email to [EMAIL PROTECTED] For more options, visit this group at http://groups.google.com/group/rubyonrails-deployment?hl=en -~----------~----~----~----~------~----~------~--~---
