On 3/26/10 1:36 PM, Roland Hänel wrote:
If I was going to write such a tool: do you think the thrift API
provides the necessary information? I think with the RandomPartitioner
you cannot scan all your rows to actually find out how big certain
ranges of rows are. And even with the OPP (that is the major target for
this kind of tool, for sure) you would have to fetch all row's content
just to find out how large it is, right?
The JMX interface exposes an Attribute which seems appropriate to this
use. It is called "TotalDiskSpaceUsed," and is available on a
per-columnfamily basis. Given a CF called "Users" in a Keyspace called
"MyKeyspace", it is accessible at :
"
org.apache.cassandra.db:type=ColumnFamilyStores,keyspace=MyKeyspace,columnfamily=Users
"
Unfortunately, I have yet to document the per-CF "ColumnFamilyStores"
and "Caches" JMX interface Attributes and Operations, including this
one. But when I do so, I will do it here :
http://wiki.apache.org/cassandra/JmxInterface
=Rob
