What is the reason for running Cassandra on Ceph? I have both running in my
environment but doing different things - Cassandra as transactional store and
Ceph as block storage for storing files.
________________________________
From: Jan<mailto:[email protected]>
Sent: 2/1/2015 2:53 AM
To: [email protected]<mailto:[email protected]>
Subject: Re: Cassandra on Ceph
Colin;
Ceph is a block based storage architecture based on RADOS. It comes with its
own replication & rebalancing along with a map of the storage layer.
Some more details & similarities: a)Ceph stores a client’s data as objects
within storage pools. (think of C* partitions)b) Using the CRUSH algorithm,
Ceph calculates which placement group should contain the object, (C* primary
keys & vnode data distribution) c) and further calculates which Ceph OSD Daemon
should store the placement group (C* node locality) d) The CRUSH algorithm
enables the Ceph Storage Cluster to scale, rebalance, and recover dynamically
(C* big table storage architecture).
Summary:
C* comes with everything that Ceph provides (with the exception of block
storage). There is no value add that Ceph brings to the table that C* does
not already provide. I seriously doubt if C* could even work out of the box
with yet another level of replication & rebalancing.
Hope this helpsJan/
C* Architect
On Saturday, January 31, 2015 7:28 PM, Colin Taylor
<[email protected]> wrote:
I may be forced to run Cassandra on top of Ceph. Does anyone have experience /
tips with this. Or alternatively, strong reasons why this won't work.
cheersColin
