Re: network compatibility from 0.6 to 0.7

2010-08-05 Thread Gary Dusbabek 
On Thu, Aug 5, 2010 at 10:05, Jonathan Ellis jbel...@gmail.com wrote:
 The situation today is that network compatibility in trunk has been
 broken without us noticing for a while now -- in CASSANDRA-956
 (according to git annotate) we changed ColumnFamily serialization in a
 non-backwards-compatible way.


956 was all about streaming, not CF serialization.  Still, it breaks
network compatibility with respect to streaming.  The IClock changes
were more likely to have broken CF serialization.

 Given the difficulty on the client side of mixing 0.6 and 0.7, most
 sites are going to end up doing a Big Bang upgrade anyway.  So is it
 really worth a lot of effort on the network protocol side?


My opinion: no.  But I don't have to upgrade a huge cluster.

Gary.

Re: network compatibility from 0.6 to 0.7

2010-08-05 Thread Jonathan Ellis 
On Thu, Aug 5, 2010 at 11:13 AM, Gary Dusbabek gdusba...@gmail.com wrote:
 On Thu, Aug 5, 2010 at 10:05, Jonathan Ellis jbel...@gmail.com wrote:
 The situation today is that network compatibility in trunk has been
 broken without us noticing for a while now -- in CASSANDRA-956
 (according to git annotate) we changed ColumnFamily serialization in a
 non-backwards-compatible way.


 956 was all about streaming, not CF serialization.  Still, it breaks
 network compatibility with respect to streaming.  The IClock changes
 were more likely to have broken CF serialization.

In ColumnFamilySerializer the very first thing we used to read/write
the CF name, and now we read/write a boolean as to whether the CF is
null instead.  That is from r947122:

remove name field from cf and clean up. Patch by Stu Hood, reviewed by
Gary Dusbabek. CASSANDRA-956

Perhaps the issue number was a typo, but either way it is logically an
extension of the CF id changes from CASSANDRA-827 so it makes more
sense to think of that as the culprit here.

There may well be other problems deeper in as you say.

-- 
Jonathan Ellis
Project Chair, Apache Cassandra
co-founder of Riptano, the source for professional Cassandra support
http://riptano.com