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From Aaron Morton <aa...@thelastpickle.com>
Subject Re: memory consuption
Date Fri, 18 Feb 2011 00:15:03 GMT
Looks like you are using virtual memory for memmapped files. Change the disk_access_mode to
standard if you want to reduce the overall memory usage. 

Aaron

On 18 Feb, 2011,at 09:34 AM, Victor Kabdebon <victor.kabdebon@gmail.com> wrote:

Sorry I forgot to say that this is the partial result of : 
ps aux | grep cassandra

Best regards

2011/2/17 Victor Kabdebon <victor.kabdebon@gmail.com>
Oh right but Cassandra doesn't really respect that, I thought there was another option to
set that

Just for your information, I set xms and xmx very low with a small amount of data. I am waiting
to be able to connect jconsole, I don't know why it is not reachable at the moment. Here is
my result :


105      26115  0.2 27.3 1125328 755316 ?      Sl   Feb09  23:58 /usr/bin/java -ea
-Xms64M -Xmx128M



2011/2/17 Aaron Morton <aaron@thelastpickle.com>
bin/cassandra.in.sh 
set Xms and Xmx in the JVM_OPTS

Aaron



On 18 Feb, 2011,at 09:10 AM, Victor Kabdebon <victor.kabdebon@gmail.com> wrote:


Is it possible to change the maximum JVM heap memory use in 0.6.X ?

2011/2/17 Aaron Morton <aaron@thelastpickle.com>
What are you using for disk_access_mode ?
Have you tried reducing the JVM head size?
Have you added the Jna.jar file to lib/ ? This will allow Cassandra to lock the JVM memory.


Aaron



On 17/02/2011, at 9:20 PM, ruslan usifov <ruslan.usifov@gmail.com> wrote:





2011/2/16 Aaron Morton <aaron@thelastpickle.com>
JVM heap memory is controlled by the settings in conf/Cassandra-env.sh

Memory mapped files will use additional virtual memory, is controlled in conf/Cassandra.yaml
disk_access_mode


And??? JVM memory heap in cassandra 0.7 is by default half of memory is system in my case
4GB, here is a part of cassandra-env.sh:

calculate_heap_size()
{
    case "`uname`" in
        Linux)
            system_memory_in_mb=`free -m | awk '/Mem:/ {print $2}'`
            MAX_HEAP_SIZE=$((system_memory_in_mb / 2))M
            return 0
        ;;
        FreeBSD)
            system_memory_in_bytes=`sysctl hw.physmem | awk '{print $2}'`
            MAX_HEAP_SIZE=$((system_memory_in_bytes / 1024 / 1024 / 2))M
            return 0
        ;;
        *)
            MAX_HEAP_SIZE=1024M
            return 1
        ;;
    esac
}



I set all this options by default. All my nodes have 8GB of memory. And i affraid that after
some time all my nodes goes to hard swap, and only reboot help them :-(((

PS: as i understand that down sometime of cassandra is normal?




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