@Tyler / @Rob, As Ashish mentioned earlier, we have 9 nodes on AWS - 6 on EastCoast and 3 on Singapore. All 9 nodes uses EC2Snitch. The current ring ( across all nodes in 2 DC ) looks like this:
ip11 - East Coast - m1.xlarge / us-east-1b - Size: 83 GB - Token: 0 ip21 - Singapore - m1.xlarge / ap-southeast-1a - Size: 88 GB - Token: 1001 ip12 - East Coast - m1.xlarge / us-east-1b - Size: 45 GB - Token: 28356863910078205288614550619314017621 ip13 - East Coast - m1.xlarge / us-east-1c - Size: 93 GB - Token: 56713727820156410577229101238628035241 ip22 - Singapore - m1.xlarge / ap-southeast-1b - Size: 73 GB - Token: 56713727820156410577229101238628036241 ip14 - East Coast - m1.xlarge / us-east-1c - Size: 20 GB - Token: 85070591730234615865843651857942052863 ip15 - East Coast - m1.xlarge / us-east-1d - Size: 89 GB - Token: 113427455640312821154458202477256070484 ip23 - Singapore - m1.xlarge / ap-southeast-1b - Size: 56 GB - Token: 113427455640312821154458202477256071484 ip16 - East Coast - m1.xlarge / us-east-1d - Size: 25 GB - Token: 141784319550391026443072753096570088105 Regarding alternating racks solution, I've the following queries: 1) By alternating racks, do you mean to alternate racks between all nodes in a single DC v/s multiple DCs? AWS EastCoast has 4 AZs and Singapore has 2 AZs. So is the final solution something like this: ip11 - East Coast - m1.xlarge / us-east-1b - Token: 0 ip21 - Singapore - m1.xlarge / ap-southeast-1a - Token: 1001 ip12 - East Coast - m1.xlarge / us-east-*1c* - Token: 28356863910078205288614550619314017621 ip13 - East Coast - m1.xlarge / us-east-*1d* - Token: 56713727820156410577229101238628035241 ip22 - Singapore - m1.xlarge / ap-southeast-1b - Token: 56713727820156410577229101238628036241 ip14 - East Coast - m1.xlarge / us-east-*1a* - Token: 85070591730234615865843651857942052863 ip15 - East Coast - m1.xlarge / us-east-*1b* - Token: 113427455640312821154458202477256070484 ip23 - Singapore - m1.xlarge / ap-southeast-*1a* - Token: 113427455640312821154458202477256071484 ip16 - East Coast - m1.xlarge / us-east-*1c* - Token: 141784319550391026443072753096570088105 Is this what you had suggested? 2) How does dynamic_snitch_badness_threshold: 0.1 effect the CPU load? On the node ( ip11 ) which was high CPU ( system load > 30 ), I checked the attribute score ( via JMX bean org.apache.cassandra.db:type=DynamicEndpointSnitch ) and saw the following: EastCoast: *ip11 = 1.6813321647677475* ip12 = 1.0003505696757231 ip13 = 1.1324160525509974 ip14 = 1.000350569675723 ip15 = 1.0007011393514456 ip16 = 1.0005258545135842 Singapore: ip21 = 1.095880806310253 ip22 = 1.4100000000000001 ip23 = 1.0953549517966696 So ip11 node is indeed having higher score - but not sure why traffic is still going to that replica as opposed to some other node? Thanks! On Fri, Nov 1, 2013 at 3:13 PM, Ashish Tyagi <tyagi.i...@gmail.com> wrote: > Hi Evan, > > The clients connect to all nodes. We tried shutting the thrift server on > the affected node. Loads did not come down. > > > > On Fri, Nov 1, 2013 at 12:59 AM, Evan Weaver <e...@fauna.org> wrote: > >> Are all your clients only connecting to your first node? I would >> probably strace it and compare the trace to one from a lightly loaded >> node. >> >> On Thu, Oct 31, 2013 at 7:12 PM, Ashish Tyagi <tyagi.i...@gmail.com> >> wrote: >> > We have a 9 node cluster. 6 nodes are in one data-center and 3 nodes in >> the >> > other. All machines are Amazon M1.XLarge configuration. >> > >> > Datacenter: DC1 >> > ========== >> > Address Rack Status State Load Owns >> > Token >> > >> > ip11 1b Up Normal 76.46 GB 16.67% 0 >> > ip12 1b Up Normal 44.66 GB 16.67% >> > 28356863910078205288614550619314017621 >> > ip13 1c Up Normal 85.94 GB 16.67% >> > 56713727820156410577229101238628035241 >> > ip14 1c Up Normal 17.55 GB 16.67% >> > 85070591730234615865843651857942052863 >> > ip15 1d Up Normal 80.74 GB 16.67% >> > 113427455640312821154458202477256070484 >> > ip16 1d Up Normal 20.88 GB 16.67% >> > 141784319550391026443072753096570088105 >> > >> > Datacenter: DC2 >> > ========== >> > Address Rack Status State Load Owns >> > Token >> > >> > ip21 1a Up Normal 78.32 GB 0.00% >> 1001 >> > ip22 1b Up Normal 71.23 GB 0.00% >> > 56713727820156410577229101238628036241 >> > ip23 1b Up Normal 53.49 GB 0.00% >> > 113427455640312821154458202477256071484 >> > >> > Problem is that node with ip address: ip11 often has 5-10 times more >> load >> > than any other node. Most of the operations are on counters. The primary >> > column family (which receives most writes) has a replication factor of >> 2 in >> > DataCenter DC1 and also in DataCenter DC2. The traffic is write heavy >> (reads >> > are less than 10% of total requests). We are using size-tiered >> compaction. >> > Both writes and reads happen with a consistency factor of LOCAL_QUORUM. >> > >> > More information: >> > >> > 1. cassandra.yaml - http://pastebin.com/u344fA6z >> > 2. Jmap heap when node under high loads - http://pastebin.com/ib3D0Pa >> > 3. Nodetool tpstats - http://pastebin.com/s0AS7bGd >> > 4. Cassandra-env.sh - http://pastebin.com/ubp4cGUx >> > 5. GC log lines - http://pastebin.com/Y0TKphsm >> > >> > Am I doing anything wrong. Any pointers will be appreciated. >> > >> > Thanks in advance, >> > Ashish >> > >