it could be the instances are IO limited. I've been running benchmarks with Cassandra 1.1.9 the last 2 weeks on a AMD FX 8 core with 32GB of ram.
with 24 threads I get roughly 20K inserts per second. each insert is only about 100-150 bytes. On Thu, Feb 14, 2013 at 8:07 AM, <ka...@comcast.net> wrote: > Using multithreading, inserting 2000 per thread, resulted in no throughput > increase. Each thread is taking about 4 seconds per, indicating a bottleneck > elsewhere. > > Ken.... > > ________________________________ > From: "Tyler Hobbs" <ty...@datastax.com> > To: user@cassandra.apache.org > Sent: Wednesday, February 13, 2013 11:06:30 AM > > Subject: Re: Write performance expectations... > > 2500 inserts per second is about what a single python thread using pycassa > can do against a local node. Are you using multiple threads for the > inserts? Multiple processes? > > > On Wed, Feb 13, 2013 at 8:21 AM, Alain RODRIGUEZ <arodr...@gmail.com> wrote: >> >> Is there a particular reason for you to use EBS ? Instance Store are >> recommended because they improve performances by reducing the I/O >> throttling. >> >> An other thing you should be aware of is that replicating the data to all >> node reduce your performance, it is more or less like if you had only one >> node (at performance level I mean). >> >> Also, writing to different datacenters probably induce some network >> latency. >> >> You should give the EC2 instance type (m1.xlarge / m1.large / ...) if you >> want some feedback about the 2500 w/s, and also give the mean size of your >> rows. >> >> Alain >> >> >> 2013/2/13 <ka...@comcast.net> >> >>> Hello, >>> New member here, and I have (yet another) question on write >>> performance. >>> >>> I'm using Apache Cassandra version 1.1, Python 2.7 and Pycassa 1.7. >>> >>> I have a cluster of 2 datacenters, each with 3 nodes, on AWS EC2 using >>> EBS and the RandomPartioner. I'm writing to a column family in a keyspace >>> that's replicated to all nodes in both datacenters, with a consistency level >>> of LOCAL_QUORUM. >>> >>> I'm seeing write performance of around 2500 rows per second. >>> >>> Is this in the ballpark for this kind of configuration? >>> >>> Thanks in advance. >>> >>> Ken.... >>> >> > > > > -- > Tyler Hobbs > DataStax
