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 <[email protected]<mailto:[email protected]>>
Reply-To: "[email protected]<mailto:[email protected]>"
<[email protected]<mailto:[email protected]>>
Date: Monday 18 March 2013 17:51
To: "[email protected]<mailto:[email protected]>"
<[email protected]<mailto:[email protected]>>
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
<[email protected]<mailto:[email protected]>>
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
<[email protected]<mailto:[email protected]>>
Date: Thursday 14 March 2013 14:25
To: "[email protected]<mailto:[email protected]>"
<[email protected]<mailto:[email protected]>>
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
