Re: Cassandra ACID

2011-06-25 Thread Peter Schuller
> We do always provide atomicity of updates in the same batch_mutate call > under a given key. Which means that for a given key, all update of the batch > will be applied, or none of them. This is *always* true and this does not > depend > on the commit log (and granted, if the write timeout, you

Re: network/message simulation framework?

2011-06-25 Thread Watanabe Maki
iptables? From iPhone On 2011/06/25, at 12:47, Yang wrote: > Thanks Jonathan. > > this provides a way to essentially get a copy of the outgoing messages, > the messages onto the real connections still go through, but I would need a > way > to shut off the real connections too. > > shutting

Re: network/message simulation framework?

2011-06-25 Thread Jonathan Ellis
On Fri, Jun 24, 2011 at 10:47 PM, Yang wrote: > Thanks Jonathan. > this provides a way to essentially get a copy of the outgoing messages, > the messages onto the real connections still go through, but I would need a > way > to shut off the real connections too. Just return null from the sink to

Re: Concurrency: Does C* support a Happened-Before relation between processes' writes?

2011-06-25 Thread Edward Capriolo
I played around with the bakery algorithm and had ok success the challenges are most implementations assume an n size array of fixed clients and when you get it working it turns out to be a good number of cassandra ops to acquire your bakery lock. On Saturday, June 25, 2011, AJ wrote: > On 6/24/2

Re: network/message simulation framework?

2011-06-25 Thread Yang
I see now that you can obtain "cheap" multiple IPs on the same box by creating virtual NICs, and then create one thrift server on each of these NIC/IPs but a remaining problem is that to do the tests, you'd have to fire up multiple JVMs, because a lot of structures in Cassandra are static, then th

Re: Concurrency: Does C* support a Happened-Before relation between processes' writes?

2011-06-25 Thread AJ
On 6/25/2011 8:24 AM, Edward Capriolo wrote: I played around with the bakery algorithm and had ok success the challenges are most implementations assume an n size array of fixed clients and when you get it working it turns out to be a good number of cassandra ops to acquire your bakery lock. I