Re: Cassandra uses more memory than Xmx

[György Dózsa <do...@gmail.com>]

Thank you, actually the mmap uses my memory. But is there a way to limit the
memory usage of mmap? Because the memory usage of Cassandra goes incredible
high (~7Gb on a 8Gb machine).

Thx
Dozsy

2010/6/16 Jonathan Ellis <jb...@gmail.com>

> you're just seeing address space used by mmap, not actually
> allocated-by-the-jvm memory.
>
> On Wed, Jun 16, 2010 at 7:02 AM, György Dózsa <do...@gmail.com> wrote:
> > Hi,
> > I have a Cassandra cluster and I set java Xmx to 2G in cassandra.in.shin
> > every node, but the memory usage of cassandra daemon is 3 or 4 times of
> that
> > (so 6-8 Gb).
> > Have you got any idea to decrease the memory usage of cassandra?
> > There are 4 nodes in the cluster and the system has approx 1000 reads and
> > writes per sec.
> > Every node has debian.
> > --
> > Thx,
> > Gyuri
> >
>
>
>
> --
> Jonathan Ellis
> Project Chair, Apache Cassandra
> co-founder of Riptano, the source for professional Cassandra support
> http://riptano.com
>



-- 
Üdv:
Gyuri

Re: Cassandra uses more memory than Xmx

[Peter Schuller <pe...@infidyne.com>]

> Thank you, actually the mmap uses my memory. But is there a way to limit the
> memory usage of mmap? Because the memory usage of Cassandra goes incredible
> high (~7Gb on a 8Gb machine).

On 64 bit platforms you don't have to worry about the total virtual
memory size of the process. If you mean the resident in-memory size,
this is entirely up to the operating system to balance and the
application has no direct control over it.

-- 
/ Peter Schuller