bloodredsun

No, the benchmark is not pure marketing. Why would you claim that it is? Apart from Astyanax, which clients are token aware?

That paper is very useful so thanks for posting the link but it has a number of issues as I see it.

1) It considers Cassandra, Redis, VoltDB, Voldermort, HBase and MySQL. It does not cover either MongoDB or Couchbase.

2) Latency values are given as average and do not show p95/p99. In my experience, Cassandra in particular is susceptible to high latency at these values.

3) Even considering average values, the read latency of Cassandra is higher than you would see with either MongoDB or Couchbase.

4) Cassandra does not deal well with ephemeral data. There are issues while GC'ing large number of tombstones for example that will hurt a long running system.

The long and short of it is that Cassandra is a fantastic system for write heavy situations. What it is not good at are read heavy situations where deterministic low latency is required, which is pretty much what the pinterest guys were dealing with.

Firstly, these sorts of applications are always going to be more read heavy so the reads are more important. Secondly, Cassandra cannot and will not be as good as something like Couchbase since the client libraries are not aware of the server topology so they cannot make direct connection to the server hosting the data. This means that depending on your consistency requirements, Cassandra will be merely okay to occasionally terrible depending on whether you care about 99th percentile. This behaviour was one of the reasons my company moved away from Cassandra

This is probably the best benchmark of Cassandra/MongoDb/Couchbase http://www.slideshare.net/renatko/couchbase-performance-benc...

By itself SOA doesn't do anything but it does free you up to do other things that allow you to scale like read-write separation and event driven or fan-out caching. One of the most important thing SOA does is that it quickly stops you from doing dirty hacks that work right now but are killers for future work. It's encapsulation at the application level

What is most interesting to me is that in many ways they have reinvented Couchbase. I think that the only reason they didn't go with this technology was the financial cost for their scale was too high.

Not if you want strong consistency. Cassandra's performance sucks in comparison with the likes of MongoDb or Couchbase when reading with strong consistency since the clients have no idea of the server topology.

So Memcached then...

It's the difference between empirical research and phenomenology and one of the things that makes Psychology a) a bit woolly compared to other sciences and b) a lot more interesting.

There actually a lot of low latency stuff being done in Java now. Using the Azul Zing JVM and tricks like the Disruptor you can do some amazing stuff.

When it came out, Spring was massively different from J2EE. "J2EE Development without EJB" was mindblowing for the Enterprise community back in 2004