Thanks, Aaron. I re-enabled hinted handoff and noted the following
* no host is marked down in nodetool ring * No host is logged as down or dead in logs * No "started hinted handoff for.." is logged * The hinted handoff manager Mbean lists pending hints to .. (drumroll) 3 non-existent nodes? Here's my ring Note: Ownership information does not include topology, please specify a keyspace. Address DC Rack Status State Load Owns Token 113427455640312821154458202477256070785 XX.XX.1.113 ione-us-atl rack1 Up Normal 382.08 GB 33.33% 0 XX.XX.31.10 ione-us-lvg rack1 Up Normal 266.04 GB 0.00% 100 XX.XX.0.71 ione-be-bru rack1 Up Normal 85.86 GB 0.00% 200 XX.XX.2.86 ione-analytics-us-atlrack1 Up Normal 153.6 GB 0.00% 300 XX.XX.1.45 ione-us-atl-ssdrack1 Up Normal 296.72 GB 0.00% 400 XX.XX.2.85 ione-analytics-us-atlrack1 Up Normal 100.3 GB 33.33% 56713727820156410577229101238628035542 XX.XX.1.204 ione-us-atl rack1 Up Normal 341.55 GB 16.67% 85070591730234615865843651857942052864 XX.XX.11 ione-us-lvg rack1 Up Normal 320.22 GB 0.00% 85070591730234615865843651857942052964 XX.XX.2.87 ione-analytics-us-atlrack1 Up Normal 166.48 GB 16.67% 113427455640312821154458202477256070785 And these are nodes pending hints according to the Mbean 166860289390734216023086131251507064403 143927757573010354572009627285182898319 24295500190543334543807902779534181373 Err.. Unbalanced ring ? Opscenter says otherwise ( "OpsCenter has detected that the token ranges are evenly distributed across the nodes in each data center. Load rebalancing is not necessary at this time." ) I appreciate your help so far! In the mean time hintedhandOFF because my mutation TP can't keep up with this traffic, not to mention compaction.. Thanks, Andras ps: all nodes are cassandra-1.1.6-dse-p1 From: aaron morton <aa...@thelastpickle.com<mailto:aa...@thelastpickle.com>> Reply-To: "user@cassandra.apache.org<mailto:user@cassandra.apache.org>" <user@cassandra.apache.org<mailto:user@cassandra.apache.org>> Date: Monday 18 March 2013 17:51 To: "user@cassandra.apache.org<mailto:user@cassandra.apache.org>" <user@cassandra.apache.org<mailto:user@cassandra.apache.org>> Subject: Re: 33million hinted handoffs from nowhere You can check which nodes hints are being held for using the JMX api. Look for the org.apache.cassandra.db:type=HintedHandoffManager MBean and call the listEndpointsPendingHints() function. There are two points where hints may be stored, if the node is down when the request started or if the node timed out and did not return before rpc_timeout. To check for the first, look for log lines about a node being "dead" on the coordinator. To check for the second look for dropped messages on the other nodes. This will be logged, or you can use nodetool tpstats to look for them. Cheers ----------------- Aaron Morton Freelance Cassandra Consultant New Zealand @aaronmorton http://www.thelastpickle.com On 15/03/2013, at 2:30 AM, Andras Szerdahelyi <andras.szerdahe...@ignitionone.com<mailto:andras.szerdahe...@ignitionone.com>> wrote: ( The previous letter was sent prematurely, sorry. ) This node is the only node being written to, but the Cfs being written replicate to almost all of the other nodes My understanding is that hinted handoff is mutations kept around on the coordinator node, to be replayed when the target node re-appears on the ring. All my nodes are up and again, no hinted handoff is logged on the node itself Thanks! Andras From: Andras Szerdahelyi <andras.szerdahe...@ignitionone.com<mailto:andras.szerdahe...@ignitionone.com>> Date: Thursday 14 March 2013 14:25 To: "user@cassandra.apache.org<mailto:user@cassandra.apache.org>" <user@cassandra.apache.org<mailto:user@cassandra.apache.org>> Subject: 33million hinted handoffs from nowhere Hi list, I am experiencing seemingly uncontrollable and unexplained growth of my HintedHandoff CF on a single node. Unexplained because there are no hinted handoffs being logged on the node, uncontrollable because I see 33 million inserts in cfstats and the size of the stables is over 10 gigs all in an hour of uptime. I have done the following to try and reproduce this: - shut down my cluster - on all nodes: remove sstables from the HintsColumnFamily data dir - on all nodes: remove commit logs - start all nodes but the one that’s showing this problem - nothing is writing to any of the nodes. There are no hinted handoff going on anywhere - bring back the node in question last - few seconds after boot: Column Family: HintsColumnFamily SSTable count: 1 Space used (live): 44946532 Space used (total): 44946532 Number of Keys (estimate): 256 Memtable Columns Count: 17840 Memtable Data Size: 17569909 Memtable Switch Count: 2 Read Count: 0 Read Latency: NaN ms. Write Count: 184836 Write Latency: 0.668 ms. Pending Tasks: 0 Bloom Filter False Postives: 0 Bloom Filter False Ratio: 0.00000 Bloom Filter Space Used: 16 Compacted row minimum size: 20924301 Compacted row maximum size: 25109160 Compacted row mean size: 25109160