cassandra-user mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From Ramzi Rabah <>
Subject Re: Potential problem with 0.5 branch (Possibly in gossiping?)
Date Wed, 23 Dec 2009 03:01:19 GMT
Hi Jaako thanks for your response.

I compiled the very latest from 0.5 branch yesterday (whatever
yesterday nights build was). I do see that Node X.X.X.X is dead, and
Node X.X.X.X has restarted.

This show up on all the 3 other servers:
 INFO [Timer-1] 2009-12-22 20:38:43,738 (line 194)
InetAddress / is now dead.

Node / has restarted, now UP again
 INFO [GMFD:1] 2009-12-22 20:43:12,812 (line 475)
Node / state jump to normal

This time the first time I restarted the node it seemed fine, but the
second time I restarted it, this is what cfstats is showing for
traffic on it :

                Column Family: Datastore
                Memtable Columns Count: 407
                Memtable Data Size: 42268
                Memtable Switch Count: 1
                Read Count: 0
                Read Latency: NaN ms.
                Write Count: 0
                Write Latency: NaN ms.
                Pending Tasks: 0

and then it went up and now it's back to:

          Column Family: Datastore
                Memtable Columns Count: 2331
                Memtable Data Size: 242364
                Memtable Switch Count: 1
                Read Count: 107
                Read Latency: 0.486 ms.
                Write Count: 113
                Write Latency: 0.000 ms.
                Pending Tasks: 0

which is half the traffic the other nodes are showing. The other 3
nodes are showing a consistent ~230 reads/writes per second, which
node 4 was showing before it was restarted. I hope data is not being
lost in the process?

On Tue, Dec 22, 2009 at 4:43 PM, Jaakko <> wrote:
> Hi,
> Which revision number you are running?
> Can you see any log lines related to node being UP or dead? (like
> "InetAddress X.X.X.X is now dead" or "Node X.X.X.X has restarted, now
> UP again"). These messages come from the Gossiper and indicate if it
> for some reason thinks the node is dead. Level of these messages is
> info.
> Another thing is: can you see any log messages like "Node X.X.X.X
> state normal, token XXX"? These are on debug level.
> -Jaakko
> On Wed, Dec 23, 2009 at 12:59 AM, Ramzi Rabah <> wrote:
>> I just recently upgraded to latest in 0.5 branch, and I am running
>> into a serious issue. I have a cluster with 4 nodes, rackunaware
>> strategy, and using my own tokens distributed evenly over the hash
>> space. I am writing/reading equally to them at an equal rate of about
>> 230 reads/writes per second(and cfstats shows that). The first 3 nodes
>> are seeds, the last one isn't. When I start all the nodes together at
>> the same time, they all receive equal amounts of reads/writes (about
>> 230).
>> When I bring node 4 down and bring it back up again, node 4's load
>> fluctuates between the 230 it used to get to sometimes no traffic at
>> all. The other 3 still have the same amount of traffic. And no errors
>> what so ever seen in logs. Any ideas what can be causing this
>> fluctuation on node 4 after I restarted it?

View raw message