TTL and Cassandra counters

2012-08-26 Thread Avi-h
Hello Our current application uses Cassandra to hold the chat items for user’s conversation and a counter of unread chat messages (per each conversation). We use TTL to delete old chat items, but we fail to see how we can define a call back which will trigger an update (decrease) to the counters’

Re: are asynchronous schema updates possible ?

2012-08-26 Thread aaron morton
Concurrent schema changes are coming in 1.2. I could not find a single issue that covered it, that may be my bad search fu. The issues for 1.2 are here https://issues.apache.org/jira/browse/CASSANDRA/fixforversion/12319262 Cheers - Aaron Morton Freelance Developer

Re: two-node cassandra cluster

2012-08-26 Thread aaron morton
most of the time and then on burst days I want to bring one more server up (with more RAM and CPU than the first) to help serve the load. Unless you are using virtual nodes (coming in 1.2) and I higher RF I would recommend using machines that have the same HW spec. Otherwise you need to

Re: Order of the cyclic group of hashed partitioners

2012-08-26 Thread aaron morton
AbstractHashedPartitioner does not exist in the trunk. https://git-wip-us.apache.org/repos/asf?p=cassandra.git;a=commitdiff;h=a89ef1ffd4cd2ee39a2751f37044dba3015d72f1 Cheers - Aaron Morton Freelance Developer @aaronmorton http://www.thelastpickle.com On 24/08/2012, at 10:51

Re: two-node cassandra cluster

2012-08-26 Thread Franc Carter
On Fri, Aug 24, 2012 at 8:25 PM, Jason Axelson ja...@engagestage.comwrote: Hi, I have an application that will be very dormant most of the time but will need high-bursting a few days out of the month. Since we are deploying on EC2 I would like to keep only one Cassandra server up most of the

Re: Cluster temporarily split into segments

2012-08-26 Thread aaron morton
using CL=ONE (read) and CL=ALL(write). Using this setting you are saying the application should fail in the case of a network partition. You are valuing Consistency and Availability over Partition Tolerance. Mixing the CL levels in response to a partition will make it difficult to reason

Re: Data Modelling Suggestions

2012-08-26 Thread aaron morton
Im finding that only the first component is used ….is this understanding correct? The result is correct. to (end)component1=timestamp3,component2=123 is less than Timestamp3: 777 Example: CREATE COLUMN FAMILY Foo WITH key_validation_class = UTF8Type AND comparator =

Decreasing the number of nodes in the ring

2012-08-26 Thread Senthilvel Rangaswamy
We have a cluster of 9 nodes in the ring. We would like SSD backed boxes. But we may not need 9 nodes in that case. What is the best way to downscale the cluster to 6 or 3 nodes. -- ..Senthil If there's anything more important than my ego around, I want it caught and shot now.

Re: Decreasing the number of nodes in the ring

2012-08-26 Thread Mohit Anchlia
use nodetool decommission and nodetool removetoken On Sun, Aug 26, 2012 at 5:31 PM, Senthilvel Rangaswamy senthil...@gmail.com wrote: We have a cluster of 9 nodes in the ring. We would like SSD backed boxes. But we may not need 9 nodes in that case. What is the best way to downscale the

Re: help required to resolve super column family problems

2012-08-26 Thread Amit Handa
Hi, i basically want to do hands-on on Super Column family concept, making some examples using hector api, and manually adding the data. I explored hector-example project, but only got very starting level of super column family example. i am in search of more super column family examples using

Re: help required to resolve super column family problems

2012-08-26 Thread Aaron Turner
On Sun, Aug 26, 2012 at 9:28 PM, Amit Handa amithand...@gmail.com wrote: Hi, i basically want to do hands-on on Super Column family concept, making some examples using hector api, and manually adding the data. I explored hector-example project, but only got very starting level of super