Just to close this item: with CASSANDRA-4314 applied I see no memory errors (either Java heap or native heap). Cassandra appears to be a hog with its memory mapped files. This caused us to wrongly think it was the culprit in a severe native memory leak. However, our leaky process was a different jsvc process altogether.
I wanted to make sure I set the record straight and not leave the idea out there that Cassandra may have a memory problem. Wade Poziombka Intel Americas, Inc. From: Poziombka, Wade L [mailto:wade.l.poziom...@intel.com] Sent: Wednesday, June 13, 2012 10:53 AM To: user@cassandra.apache.org Subject: RE: Much more native memory used by Cassandra then the configured JVM heap size Seems like my only recourse is to remove jna.jar and just take the performance/swapping pain? Obviously can't have the entire box lock up. I can provide a pmap etc. if needed. From: Poziombka, Wade L [mailto:wade.l.poziom...@intel.com] Sent: Wednesday, June 13, 2012 10:28 AM To: user@cassandra.apache.org<mailto:user@cassandra.apache.org> Subject: RE: Much more native memory used by Cassandra then the configured JVM heap size I have experienced the same issue. The Java heap seems fine but eventually the OS runs out of heap. In my case it renders the entire box unusable without a hard reboot. Console shows: is there a way to limit the native heap usage? xfs invoked oom-killer: gfp_mask=0x201d2, order=0, oomkilladj=0 Call Trace: [<ffffffff800c9d3a>] out_of_memory+0x8e/0x2f3 [<ffffffff8002dfd7>] __wake_up+0x38/0x4f [<ffffffff8000f677>] __alloc_pages+0x27f/0x308 [<ffffffff80013034>] __do_page_cache_readahead+0x96/0x17b [<ffffffff80013971>] filemap_nopage+0x14c/0x360 [<ffffffff8000896c>] __handle_mm_fault+0x1fd/0x103b [<ffffffff8002dfd7>] __wake_up+0x38/0x4f [<ffffffff800671f2>] do_page_fault+0x499/0x842 [<ffffffff800b8f39>] audit_filter_syscall+0x87/0xad [<ffffffff8005dde9>] error_exit+0x0/0x84 Node 0 DMA per-cpu: empty Node 0 DMA32 per-cpu: empty Node 0 Normal per-cpu: cpu 0 hot: high 186, batch 31 used:23 cpu 0 cold: high 62, batch 15 used:14 ... cpu 23 cold: high 62, batch 15 used:8 Node 1 HighMem per-cpu: empty Free pages: 158332kB (0kB HighMem) Active:16225503 inactive:1 dirty:0 writeback:0 unstable:0 free:39583 slab:21496 Node 0 DMA free:0kB min:0kB low:0kB high:0kB active:0kB inactive:0kB present:0kB lowmem_reserve[]: 0 0 32320 32320 Node 0 DMA32 free:0kB min:0kB low:0kB high:0kB active:0kB inactive:0kB present:0 lowmem_reserve[]: 0 0 32320 32320 Node 0 Normal free:16136kB min:16272kB low:20340kB high:24408kB active:3255624 From: aaron morton [mailto:aa...@thelastpickle.com] Sent: Tuesday, June 12, 2012 4:08 AM To: user@cassandra.apache.org<mailto:user@cassandra.apache.org> Subject: Re: Much more native memory used by Cassandra then the configured JVM heap size see http://wiki.apache.org/cassandra/FAQ#mmap which cause the OS low memory. If the memory is used for mmapped access the os can get it back later. Is the low free memory causing a problem ? Cheers ----------------- Aaron Morton Freelance Developer @aaronmorton http://www.thelastpickle.com On 12/06/2012, at 5:52 PM, Jason Tang wrote: Hi I found some information of this issue And seems we can have other strategy for data access to reduce mmap usage, in order to use less memory. But I didn't find the document to describe the parameters for Cassandra 1.x, is it a good way to use this parameter to reduce shared memory usage and what's the impact? (btw, our data model is dynamical, which means the although the through put is high, but the life cycle of the data is short, one hour or less). " # Choices are auto, standard, mmap, and mmap_index_only. disk_access_mode: auto " http://comments.gmane.org/gmane.comp.db.cassandra.user/7390 2012/6/12 Jason Tang <ares.t...@gmail.com<mailto:ares.t...@gmail.com>> See my post, I limit the HVM heap 6G, but actually Cassandra will use more memory which is not calculated in JVM heap. I use top to monitor total memory used by Cassandra. ============================= -Xms6G -Xmx6G -Xmn1600M 2012/6/12 Jeffrey Kesselman <jef...@gmail.com<mailto:jef...@gmail.com>> Btw. I suggest you spin up JConsole as it will give you much more detai kon what your VM is actually doing. On Mon, Jun 11, 2012 at 9:14 PM, Jason Tang <ares.t...@gmail.com<mailto:ares.t...@gmail.com>> wrote: Hi We have some problem with Cassandra memory usage, we configure the JVM HEAP 6G, but after runing Cassandra for several hours (insert, update, delete). The total memory used by Cassandra go up to 15G, which cause the OS low memory. So I wonder if it is normal to have so many memory used by cassandra? And how to limit the native memory used by Cassandra? =========================== Cassandra 1.0.3, 64 bit jdk. Memory ocupied by Cassandra 15G PID USER PR NI VIRT RES SHR S %CPU %MEM TIME+ COMMAND 9567 casadm 20 0 28.3g 15g 9.1g S 269 65.1 385:57.65 java ============================= -Xms6G -Xmx6G -Xmn1600M # ps -ef | grep 9567 casadm 9567 1 55 Jun11 ? 05:59:44 /opt/jdk1.6.0_29/bin/java -ea -javaagent:/opt/dve/cassandra/bin/../lib/jamm-0.2.5.jar -XX:+UseThreadPriorities -XX:ThreadPriorityPolicy=42 -Xms6G -Xmx6G -Xmn1600M -XX:+HeapDumpOnOutOfMemoryError -Xss128k -XX:+UseParNewGC -XX:+UseConcMarkSweepGC -XX:+CMSParallelRemarkEnabled -XX:SurvivorRatio=8 -XX:MaxTenuringThreshold=1 -XX:CMSInitiatingOccupancyFraction=75 -XX:+UseCMSInitiatingOccupancyOnly -Djava.net.preferIPv4Stack=true -Dcom.sun.management.jmxremote.port=6080 -Dcom.sun.management.jmxremote.ssl=false -Dcom.sun.management.jmxremote.authenticate=false -Daccess.properties=/opt/dve/cassandra/conf/access.properties -Dpasswd.properties=/opt/dve/cassandra/conf/passwd.properties -Dpasswd.mode=MD5 -Dlog4j.configuration=log4j-server.properties -Dlog4j.defaultInitOverride=true -cp /opt/dve/cassandra/bin/../conf:/opt/dve/cassandra/bin/../build/classes/main:/opt/dve/cassandra/bin/../build/classes/thrift:/opt/dve/cassandra/bin/../lib/Cassandra-Extensions-1.0.0.jar:/opt/dve/cassandra/bin/../lib/antlr-3.2.jar:/opt/dve/cassandra/bin/../lib/apache-cassandra-1.0.3.jar:/opt/dve/cassandra/bin/../lib/apache-cassandra-clientutil-1.0.3.jar:/opt/dve/cassandra/bin/../lib/apache-cassandra-thrift-1.0.3.jar:/opt/dve/cassandra/bin/../lib/avro-1.4.0-fixes.jar:/opt/dve/cassandra/bin/../lib/avro-1.4.0-sources-fixes.jar:/opt/dve/cassandra/bin/../lib/commons-cli-1.1.jar:/opt/dve/cassandra/bin/../lib/commons-codec-1.2.jar:/opt/dve/cassandra/bin/../lib/commons-lang-2.4.jar:/opt/dve/cassandra/bin/../lib/compress-lzf-0.8.4.jar:/opt/dve/cassandra/bin/../lib/concurrentlinkedhashmap-lru-1.2.jar:/opt/dve/cassandra/bin/../lib/guava-r08.jar:/opt/dve/cassandra/bin/../lib/high-scale-lib-1.1.2.jar:/opt/dve/cassandra/bin/../lib/jackson-core-asl-1.4.0.jar:/opt/dve/cassandra/bin/../lib/jackson-mapper-asl-1.4.0.jar:/opt/dve/cassandra/bin/../lib/jamm-0.2.5.jar:/opt/dve/cassandra/bin/../lib/jline-0.9.94.jar:/opt/dve/cassandra/bin/../lib/json-simple-1.1.jar:/opt/dve/cassandra/bin/../lib/libthrift-0.6.jar:/opt/dve/cassandra/bin/../lib/log4j-1.2.16.jar:/opt/dve/cassandra/bin/../lib/servlet-api-2.5-20081211.jar:/opt/dve/cassandra/bin/../lib/slf4j-api-1.6.1.jar:/opt/dve/cassandra/bin/../lib/slf4j-log4j12-1.6.1.jar:/opt/dve/cassandra/bin/../lib/snakeyaml-1.6.jar:/opt/dve/cassandra/bin/../lib/snappy-java-1.0.4.1.jar org.apache.cassandra.thrift.CassandraDaemon ============================== # nodetool -h 127.0.0.1 -p 6080 info Token : 85070591730234615865843651857942052864 Gossip active : true Load : 20.59 GB Generation No : 1339423322 Uptime (seconds) : 39626 Heap Memory (MB) : 3418.42 / 5984.00 Data Center : datacenter1 Rack : rack1 Exceptions : 0 ============================= All row cache and key cache are disabled by default Key cache: disabled Row cache: disabled ============================== # pmap 9567 9567: java START SIZE RSS PSS DIRTY SWAP PERM MAPPING 0000000040000000 36K 36K 36K 0K 0K r-xp /opt/jdk1.6.0_29/bin/java 0000000040108000 8K 8K 8K 8K 0K rwxp /opt/jdk1.6.0_29/bin/java 000000004010a000 18040K 17988K 17988K 17988K 0K rwxp [heap] 000000067ae00000 6326700K 6258664K 6258664K 6258664K 0K rwxp [anon] 00000007fd06b000 48724K 0K 0K 0K 0K rwxp [anon] 00007fbed1530000 1331104K 0K 0K 0K 0K r-xs /var/cassandra/data/drc/queue-hb-219-Data.db 00007fbf22918000 2097152K 0K 0K 0K 0K r-xs /var/cassandra/data/drc/queue-hb-219-Data.db 00007fbfa2918000 2097148K 1124464K 1124462K 0K 0K r-xs /var/cassandra/data/drc/queue-hb-219-Data.db 00007fc022917000 2097156K 2096496K 2096492K 0K 0K r-xs /var/cassandra/data/drc/queue-hb-219-Data.db 00007fc0a2918000 2097148K 2097148K 2097146K 0K 0K r-xs /var/cassandra/data/drc/queue-hb-219-Data.db 00007fc1a2917000 733584K 6444K 6444K 0K 0K r-xs /var/cassandra/data/drc/queue-hb-109-Data.db 00007fc1cf57b000 2097148K 20980K 20980K 0K 0K r-xs /var/cassandra/data/drc/queue-hb-109-Data.db 00007fc24f57a000 2097152K 456480K 456478K 0K 0K r-xs /var/cassandra/data/drc/queue-hb-109-Data.db 00007fc2cf57a000 2097156K 1168320K 1168318K 0K 0K r-xs /var/cassandra/data/drc/queue-hb-109-Data.db 00007fc34f57b000 2097148K 1177520K 1177520K 0K 0K r-xs /var/cassandra/data/drc/queue-hb-109-Data.db 00007fc405629000 618708K 338248K 338248K 0K 0K r-xs /var/cassandra/data/drc/queue-hb-230-Data.db 00007fc42b25e000 620388K 289024K 289024K 0K 0K r-xs /var/cassandra/data/drc/queue-hb-224-Data.db 00007fc451037000 619160K 342108K 342108K 0K 0K r-xs /var/cassandra/data/drc/queue-hb-216-Data.db 00007fc62b7df000 132696K 0K 0K 0K 0K r-xs /var/cassandra/data/drc/queue.idxInQueueTime-hb-175-Data.db 00007fc6de8e0000 132696K 0K 0K 0K 0K r-xs /var/cassandra/data/drc/queue.idxRecvTime-hb-175-Data.db 00007fc6f2bcc000 52492K 0K 0K 0K 0K r-xs /var/cassandra/data/drc/queue.idxPartitionId-hb-211-Data.db 00007fc6f64dc000 43784K 40840K 40840K 0K 0K r-xs /var/cassandra/data/drc/fpr_index-hb-91-Data.db 00007fc707ca6000 68968K 37724K 37724K 0K 0K r-xs /var/cassandra/data/drc/queue-hb-219-Index.db 00007fc70c000000 2468K 2436K 2436K 2436K 0K rwxp [anon] 00007fc70c269000 63068K 0K 0K 0K 0K ---p [anon] 00007fc710b9e000 52888K 0K 0K 0K 0K r-xs /var/cassandra/data/drc/queue.idxInQueueTime-hb-216-Data.db 00007fc713f44000 52952K 0K 0K 0K 0K r-xs /var/cassandra/data/drc/queue.idxFireTimeRange-hb-140-Data.db 00007fc7172fa000 52952K 0K 0K 0K 0K r-xs /var/cassandra/data/drc/queue.idxFireTime-hb-140-Data.db 00007fc71bd13000 162992K 162984K 162984K 0K 0K r-xs /var/cassandra/data/drc/fpr_index-hb-80-Data.db 00007fc725c3f000 52952K 28712K 28712K 0K 0K r-xs /var/cassandra/data/drc/queue.idxInQueueTimeRange-hb-140-Data.db 00007fc728ff5000 52952K 0K 0K 0K 0K r-xs /var/cassandra/data/drc/queue.idxRecvTimeRange-hb-140-Data.db 00007fc72d026000 52480K 0K 0K 0K 0K r-xs /var/cassandra/data/drc/queue.idxRecvTimeRange-hb-211-Data.db 00007fc730366000 52564K 0K 0K 0K 0K r-xs /var/cassandra/data/drc/queue.idxStatus-hb-196-Data.db 00007fc7336bb000 22348K 0K 0K 0K 0K r-xs /var/cassandra/data/drc/queue.idxInQueueTime-hb-175-Index.db BRs //Ares Tang -- It's always darkest just before you are eaten by a grue.
