What type of snitch are you using for cassandra.yaml: endpoint_snitch ? PropertyFileSnitch can improve performance.
- bharat On Tue, Mar 31, 2015 at 1:59 PM, daemeon reiydelle <daeme...@gmail.com> wrote: > What is your replication factor? > > Any idea how much data has to be processed under the query? > > With that few nodes (3) in each DC, even with replication=1, you are > probably not getting much inter-node data transfer in a local quorum, until > of course you do cross data centers and at least one full copy of the data > has to come across the wire. > > While running the query against both DC's, you can take a look at netstats > to get a really quick-and-dirty idea of network traffic. > > > > *.......* > > > > > > > *“Life should not be a journey to the grave with the intention of arriving > safely in apretty and well preserved body, but rather to skid in broadside > in a cloud of smoke,thoroughly used up, totally worn out, and loudly > proclaiming “Wow! What a Ride!” - Hunter ThompsonDaemeon C.M. ReiydelleUSA > (+1) 415.501.0198 <%28%2B1%29%20415.501.0198>London (+44) (0) 20 8144 9872 > <%28%2B44%29%20%280%29%2020%208144%209872>* > > On Tue, Mar 31, 2015 at 1:54 PM, Andrew Vant <andrew.v...@rackspace.com> > wrote: > >> I have a Cassandra 2.0.13 cluster with three datacenters, three nodes per >> datacenter. If I open cqlsh and do a select with any consistency level that >> crosses datacenters (e.g. QUORUM or ALL), it works, but takes 2+ minutes to >> return. The same statement with consistency ONE or LOCAL_QUORUM is as fast >> as it should be. It does not appear to be latency between centers; I can >> point cqlsh at a server in a different DC and it's not noticeably slow. >> >> I tried turning tracing on to get a better idea of what was happening; >> but it complains `Session <long hex string> wasn't found`. >> >> I'm not entirely sure what direction to look in to find the problem. >> >> -- >> >> Andrew > > >
