Hi,

I'm facing a problem in Cassandra cluster deployed on EC2 where the node is
going down under write load.

I have configured a cluster of 4 Large EC2 nodes with RF of 2.
All nodes are instance storage backed. DISK is RAID0 with 800GB

I'm pumping in write requests at about 4000 writes/sec. One of the node
went down under this load. The total data size in each node was not more
than 7GB
Got the following WARN messages in the LOG file...

1. setting live ratio to minimum of 1.0 instead of 0.9003153296009601
2. Heap is 0.7515559786053904 full.  You may need to reduce memtable and/or
cache sizes.  Cassandra will now flush up to the two largest memtables to
free up memory.  Adjust flush_largest_memtables_at threshold in
cassandra.yaml if you don't want Cassandra to do
this automatically
3. WARN [CompactionExecutor:570] 2012-09-14 11:45:12,024
CompactionTask.java (line 84) insufficient space to compact all requested
files

All cassandra settings are default settings.
Do i need to tune anything to support this write rate?

Thanks
Rohit

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