On 12/5/10 3:52 PM, James A. Donald wrote:
>
> A centralized coordinator is single point of failure and an additional
> configuration issue. If everyone runs the same algorithm, they will
> mostly agree without need for a central coordinator - though there
> will never be 100% agreement. If the sy
On 2010-12-06 4:43 AM, Ravi Pinjala wrote:
I'm pretty sure Ceph runs CRUSH on the servers, too - it's how they
handle rebalancing, after all. The biggest issue I see there is that
the way they use it depends on setting a new CRUSH map across the
entire cluster atomically, which only works on Ceph
I'm pretty sure Ceph runs CRUSH on the servers, too - it's how they
handle rebalancing, after all. The biggest issue I see there is that
the way they use it depends on setting a new CRUSH map across the
entire cluster atomically, which only works on Ceph because they use a
Paxos cluster to coordina
Ravi Pinjala writes:
> As far as description languages for data allocation go, Ceph has
> already solved this problem - check out the "CRUSH" algorithm.
> Basically, it's a description language for data placement that
> controls replication and data placement, and I think it also lets
> clients
CRUSH seems to require knowledge of a hierarchy (location) of devices
(location, racks, etc). I'm not sure this knowledge is available to
tahoe. Or any knowledge we have should be assumed as flat.
http://ceph.newdream.net/wiki/Custom_data_placement_with_CRUSH
Terrell
On 12/5/10 4:42 AM, Ravi
As far as description languages for data allocation go, Ceph has
already solved this problem - check out the "CRUSH" algorithm.
Basically, it's a description language for data placement that
controls replication and data placement, and I think it also lets
clients figure out which servers a piece o
Hi,
As the answer of this discussion, Tahoe doesn't have automatic rebalancing
capability now.
http://tahoe-lafs.org/pipermail/tahoe-dev/2010-December/005697.html
Also, we have bunch of tickets already tracking this problem. Such as the
rebalancing manager:
http://tahoe-lafs.org/trac/tahoe-lafs/t
