Hm - had to digg deeper and it totally looks like a native mem leak to me:
We are still growing with res += 100MB a day. Cassandra is > 8G now
I checked the cassandra process with pmap -x
Here's the human readable (aggregated) output:
Format is thingy: RSS in KB
Total RSS: 8478376
Here's a little more detail:
SSTables (data and index files)
Maybe the output of pmap is totally misleading but my interpretation is that only 2GB of RSS is attributed to paged in sstables.
I have one large anon block which looks like this:
Address Kbytes RSS Dirty Mode Mapping
000000073f600000 0 3093248 3093248 rwx-- [ anon ]
This is the native heap thats been allocated on startup and mlocked
So theres still 3.5GB of anon memory.
As I said mem goes up by 100MB each day pretty linearly.
Would be great if anyone could verify this by running pmap or talk my off the roof by explaining that nothing's the way it seems.
All this might be heavily OS specific so maybe that's only on Debian?
Thanks a lot
On Jul 4, 2011, at 2:42 PM, Jonathan Ellis wrote:
mmap'd data will be attributed to res, but the OS can page it out
instead of killing the process.
On Mon, Jul 4, 2011 at 5:52 AM, Daniel Doubleday
we have a mem problem with cassandra. res goes up without bounds (well until
the os kills the process because we dont have swap)
I found a thread that's about the same problem but on OpenJDK:
We are on Debian with Sun JDK.
Resident mem is 7.4G while heap is restricted to 3G.
Anyone else is seeing this with Sun JDK?
:/home/dd# java -version
java version "1.6.0_24"
Java(TM) SE Runtime Environment (build 1.6.0_24-b07)
Java HotSpot(TM) 64-Bit Server VM (build 19.1-b02, mixed mode)
:/home/dd# ps aux |grep java
cass 28201 9.5 46.8 372659544 7707172 ? SLl May24 5656:21
/usr/bin/java -ea -XX:+UseThreadPriorities -XX:ThreadPriorityPolicy=42
-Xms3000M -Xmx3000M -Xmn400M ...
PID USER PR NI VIRT RES SHR S %CPU %MEM TIME+ COMMAND
28201 cass 20 0 355g 7.4g 1.4g S 8 46.9 5656:25 java
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