I have a cluster of 3 0.7 beta 2 nodes (built today from the latest trunk)
running on Large, EBS-backed, x64 EC2 instances; RF=3. I attempted to write
somewhere near 500,000 records every 15 minutes from a total of 5 different
computers (using Pelops and multi-threading). Though my network blew up
and I'm not quite sure how many records were inserted, I lost a node a
couple hours later, and the other 2 were at severely high memory useage. Is
this a memory leak of some kind, or something I can configure / watch for in
the future?
A nodetool does this:
[ec2-u...@xxx bin]$ ./nodetool -h localhost ring
Address Status State Load Token
XXX
ipXXX Down Normal 564.76 MB XXX
ipXXX Up Normal 564.83 MB XXX
ipXXX Up Normal 563.06 MB XXX
A top on the box that is down shows this: (dual core x64)
Cpu(s): 19.9%us, 5.9%sy, 0.0%ni, 8.8%id, 57.3%wa, 0.0%hi, 0.0%si,
8.1%st
Mem: 7651528k total, 7611112k used, 40416k free, 66056k buffers
Swap: 0k total, 0k used, 0k free, 3294076k cached
PID USER PR NI VIRT RES SHR S %CPU %MEM TIME+ COMMAND
22514 root 20 0 5790m 4.0g 167m S 91.9 54.8 152:45.08 java
I see this error in the log file:
ERROR [CompactionExecutor:1] 2010-10-21 01:35:05,318
AbstractCassandraDaemon.java (line 88) Fatal exception in thread
Thread[CompactionExecutor:1,1,main]
java.io.IOError: java.io.IOException: Cannot run program "ln":
java.io.IOException: error=12, Cannot allocate memory
at
org.apache.cassandra.db.ColumnFamilyStore.snapshot(ColumnFamilyStore.java:1368)
at org.apache.cassandra.db.Table.snapshot(Table.java:163)
at
org.apache.cassandra.db.CompactionManager.doCompaction(CompactionManager.java:232)
at
org.apache.cassandra.db.CompactionManager$1.call(CompactionManager.java:106)
at
org.apache.cassandra.db.CompactionManager$1.call(CompactionManager.java:84)
at java.util.concurrent.FutureTask$Sync.innerRun(FutureTask.java:334)
at java.util.concurrent.FutureTask.run(FutureTask.java:166)
at
java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1110)
at
java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:603)
at java.lang.Thread.run(Thread.java:636)
Caused by: java.io.IOException: Cannot run program "ln":
java.io.IOException: error=12, Cannot allocate memory
at java.lang.ProcessBuilder.start(ProcessBuilder.java:475)
at
org.apache.cassandra.io.util.FileUtils.createHardLinkWithExec(FileUtils.java:263)
at org.apache.cassandra.io.util.FileUtils.createHardLink(FileUtils.java:229)
at
org.apache.cassandra.db.ColumnFamilyStore.snapshot(ColumnFamilyStore.java:1360)
... 9 more
Caused by: java.io.IOException: java.io.IOException: error=12, Cannot
allocate memory
at java.lang.UNIXProcess.<init>(UNIXProcess.java:164)
at java.lang.ProcessImpl.start(ProcessImpl.java:81)
at java.lang.ProcessBuilder.start(ProcessBuilder.java:468)
... 12 more
On Wed, Oct 20, 2010 at 3:16 PM, Jonathan Ellis <jbel...@gmail.com> wrote:
> can you reproduce this by, say, running nodeprobe ring in a bash while
> loop?
>
> On Wed, Oct 20, 2010 at 3:09 PM, Bill Au <bill.w...@gmail.com> wrote:
> > One of my Cassandra server crashed with the following:
> >
> > ERROR [ACCEPT-xxx.xxx.xxx/nnn.nnn.nnn.nnn] 2010-10-19 00:25:10,419
> > CassandraDaemon.java (line 82) Uncaught exception in thread
> > Thread[ACCEPT-xxx.xxx.xxx/nnn.nnn.nnn.nnn,5,main]
> > java.lang.OutOfMemoryError: unable to create new native thread
> > at java.lang.Thread.start0(Native Method)
> > at java.lang.Thread.start(Thread.java:597)
> > at
> >
> org.apache.cassandra.net.MessagingService$SocketThread.run(MessagingService.java:533)
> >
> >
> > I took threads dump in the JVM on all the other Cassandra severs in my
> > cluster. They all have thousand of threads looking like this:
> >
> > "JMX server connection timeout 183373" daemon prio=10
> tid=0x00002aad230db800
> > nid=0x5cf6 in Object.wait() [0x00002aad7a316000]
> > java.lang.Thread.State: TIMED_WAITING (on object monitor)
> > at java.lang.Object.wait(Native Method)
> > at
> >
> com.sun.jmx.remote.internal.ServerCommunicatorAdmin$Timeout.run(ServerCommunicatorAdmin.java:150)
> > - locked <0x00002aab056ccee0> (a [I)
> > at java.lang.Thread.run(Thread.java:619)
> >
> > It seems to me that there is a JMX threads leak in Cassandra. NodeProbe
> > creates a JMXConnector but never calls its close() method. I tried
> setting
> > jmx.remote.x.server.connection.timeout to 0 hoping that would disable the
> > JMX server connection timeout threads. But that did not make any
> > difference.
> >
> > Has anyone else seen this?
> >
> > Bill
> >
>
>
>
> --
> Jonathan Ellis
> Project Chair, Apache Cassandra
> co-founder of Riptano, the source for professional Cassandra support
> http://riptano.com
>
