+1.  We are trying to figure that all out too.

I don't know if it helps but we finally upgraded to 1.2.2 which is supposed to 
have better LCS support from what I understand.  We did lots of QA testing and 
jumped from 1.1.4.  Rolling restart did not work at all in QA so we went with 
take the whole cluster down instead and used these steps after having a 
cassandra-1.2.2 deployed and updating all property files correctly as well.  
(snapshot had to be done before drain oddly enough :( :( since drain seemed to 
shut down some ports that nodetool couldn't work).

#on the node itself
clush -g datanodes -l cassandra nodetool -h localhost -p 7199 snapshot databus5 
-t 1.2.2a
#drain shuts down ports so you can't do a snapshot....
clush -g datanodes -l cassandra nodetool drain
#AS ROOT...
./cassandraStop.sh
clush -g datanodes rm /opt/cassandra
clush -g datanodes ln -s /opt/cassandra-1.2.2 /opt/cassandra
#BACK to cassandra(it won't run as root anyways as not in path)
cassandraStart.sh



From: Alain RODRIGUEZ <arodr...@gmail.com<mailto:arodr...@gmail.com>>
Reply-To: "user@cassandra.apache.org<mailto:user@cassandra.apache.org>" 
<user@cassandra.apache.org<mailto:user@cassandra.apache.org>>
Date: Tuesday, March 5, 2013 9:50 AM
To: "user@cassandra.apache.org<mailto:user@cassandra.apache.org>" 
<user@cassandra.apache.org<mailto:user@cassandra.apache.org>>
Subject: Re: LCS and counters

Well no one says my assertion is false, so it is probably true.

Going further, what would be the steps to migrate from STC to LCS ? Is there 
any precautions to take doing it using C*1.1.6 (like removing commit logs since 
drain is broken) ?

Any insight or link on this procedure would be appreciated.


2013/2/25 Janne Jalkanen 
<janne.jalka...@ecyrd.com<mailto:janne.jalka...@ecyrd.com>>

At least for our use case (reading slices from varyingly sized rows from 
10-100k composite columns with counters and hundreds of writes/second) LCS has 
a nice ~75% lower read latency than Size Tiered. And compactions don't stop the 
world anymore.  Repairs do easily trigger a few hundred compactions though, but 
it's not that bad.

/Janne

On Feb 25, 2013, at 17:10 , Alain RODRIGUEZ 
<arodr...@gmail.com<mailto:arodr...@gmail.com>> wrote:

> Hi
>
> I am just wondering... Wouldn't it always be worth it to use LCS on counter 
> CF since LCS is optimized for reads and that writing a counter always require 
> a read ?
>
> Alain


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