Re: High disk io read load

Erm sorry, forgot to mention. In this case "cas10" is Node A with 512 tokens and "cas9" Node B with 256 tokens. 2017-02-16 6:38 GMT+01:00 Benjamin Roth : > It doesn't really look like that: > https://cl.ly/2c3Z1u2k0u2I > > Thats the ReadLatency.count metric aggregated by

Re: High disk io read load

It doesn't really look like that: https://cl.ly/2c3Z1u2k0u2I Thats the ReadLatency.count metric aggregated by host which represents the actual read operations, correct? 2017-02-15 23:01 GMT+01:00 Edward Capriolo : > I think it has more than double the load. It is double

Re: Problems with large partitions and compaction

What Cassandra version? CMS or G1? What are your timeouts set to? "GC activity" - Even if there isn't a lot of activity per se maybe there is a single long pause happening. I have seen large partitions cause lots of allocation fast. Looking at SSTable Levels in nodetool cfstats can help, look

Re: High disk io read load

I think it has more than double the load. It is double the data. More read repair chances. More load can swing it's way during node failures etc. On Wednesday, February 15, 2017, Benjamin Roth wrote: > Hi there, > > Following situation in cluster with 10 nodes: > Node

High disk io read load

Hi there, Following situation in cluster with 10 nodes: Node A's disk read IO is ~20 times higher than the read load of node B. The nodes are exactly the same except: - Node A has 512 tokens and Node B 256. So it has double the load (data). - Node A also has 2 SSDs, Node B only 1 SSD (according

RE: Current data density limits with Open Source Cassandra

I request 1-2 TB of disk per node, depending on how large the data is estimated to be (for larger data, 2 TB). I have some dense nodes (4+ TB of disk available). They are harder to manage for repairs, bootstrapping, compaction, etc. because it takes so long to stream the data, etc. For the

Re: Discrete events table - Partition Question

​Hello, ​I don't see any impact in your case (a table without composite key). But it can be less flexible on your query-pattern, in this case you can't return an event by date... for example! but if you'r sure that you will query only by id_event, in this case, no problems.

Discrete events table - Partition Question

Hello everyone - I have a modeling challenge where we are recording events about 1000 a sec in a Cassandra table. The event id is unique and is being used as a partition key with no clustering columns. I understand this is a anti pattern and will result in discrete partitions. The question I

Re: Determining if data will be created on Cassandra Write Exceptions

Hi Rouble, I usually have to read javadoc in java driver to get my ideas straight regarding exception handling. You can find informations reading : http://docs.datastax.com/en/drivers/java/3.1/com/datastax/driver/core/policies/RetryPolicy.html and for instance