Do you shuffle the replicas with 
TokenAwarePolicy?TokenAwarePolicy(LoadBalancingPolicy childPolicy, boolean 

Romain    Le Mardi 20 septembre 2016 15h47, Pranay akula 
<pranay.akula2...@gmail.com> a écrit :

 I was a able to find the hotspots causing the load,but the size of these 
partitions are in KB and no tombstones and no.of sstables is only 2 what else i 
need to debug to find the reason for high load for some nodes.  we are also 
using unlogged batches is that can be the reason ?? how to find which node is 
serving as a coordinator for un logged batches?? we are using token-aware 

On Mon, Sep 19, 2016 at 12:29 PM, Pranay akula <pranay.akula2...@gmail.com> 

I was able to see most used partitions but the nodes with less load are serving 
more read and write requests for that particular partitions when compared to 
nodes with high load, how can i find if these nodes are serving as 
co-coordinators for those read and write requests ?? how can i find the token 
range for these particular partitions and which node is the primary for these 
partition ??

On Mon, Sep 19, 2016 at 11:04 AM, Pranay akula <pranay.akula2...@gmail.com> 

Hai Jeff,
Thank, we are using RF 3 and cassandra version 2.1.8.
On Mon, Sep 19, 2016 at 10:55 AM, Jeff Jirsa <jeff.ji...@crowdstrike.com> wrote:

Is your replication_factor 2? Or is it 3?  What version are you using?  The 
most likely answer is some individual partition that’s either being 
written/read more than others, or is somehow impacting the cluster (wide rows 
are a natural candidate). You don’t mention your version, but most modern 
versions of Cassandra ship with ‘nodetool toppartitions’, which will help you 
identify frequently written/read partitions – perhaps you can use that to 
identify a hotspot due to some external behavior (some partition being read 
thousands of times, over and over could certainly drive up load). -          
Jeff From: Pranay akula <pranay.akula2...@gmail.com>
Reply-To: "user@cassandra.apache.org" <user@cassandra.apache.org>
Date: Monday, September 19, 2016 at 7:53 AM
To: "user@cassandra.apache.org" <user@cassandra.apache.org>
Subject: High load on few nodes in a DC. when our cluster was under load  i am 
seeing  1 or 2 nodes are on more load consistently when compared to others in 
dc i am not seeing any GC pauses or wide partitions  is this can be those nodes 
are continuously serving as coordinators ?? how can  i find what is the reason 
for high load on those two nodes ?? We are using Vnode.   ThanksPranay. 


Reply via email to