[Sheepdog] some questions about sheepdog

[Frank Doege]

Hi List,


At first, this really looks like a great project and I feel also that its very alive, so I am planning to do a test installation of sheepdog storage backed
KVM

I have already read what I could find about this project however there is not so much documentation out there yet.

I have a couple of questions, I would appreciate if someone could enlighten me :-)

1.
 sheepdog needs at least two storage nodes to work, data is distributed like in a RAID1 therefore I always need 
the double of the capacity I plan to use for kvm guests, is there a Parity option that works like RAID5 ?

2. 
Does anyone has some performance numbers, with two nodes and 8HDD SAS Raid5 dual Gbit network bond
What can I get for an estimated performance ? What is the bottleneck here, the network or the disks ?

3. 
Sheepdog uses the network to connect to the nodes, I guess it balances data in chunks over all available nodes, in the moment
It stores each chunk on a node and a copy on another node, is this rotated over all nodes or is each image fixed on two nodes ?

4.
As sheepdog uses the network as a transport medium am how high is the latency, is this an issue in production networks ?

Thanks & Greetings,

Frank