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Posted to user@cassandra.apache.org by Ananth Gundabattula <ag...@gmail.com> on 2012/10/04 04:21:32 UTC
Regarding Row Cache configuration and non-heap memory
Hello,
I have configured cassandra 1.1.4 to use row cache of 10GB ( the RAM on the
machine is pretty big and hence the row cache size is high). My heap
settings are 8G and new heap size is 1600M.
As I read from the forum and documentation, jna.jar allows to use non-heap
memory for the row caches.
The question I have is how is the configuration in cassandra.yaml for
row_cache_size_in_mb interpreted? Is it referring to the non-heap setting
or the memory used inside the heap to maintain book-keeping information
about the non-heap memory ( as I gather from the postings that heap is
indeed used to some extent while still using the non-heap memory for row
caches).
In short the question is whether the row_cache_size_in_mb can exceed the
heap setting for cassandra 1.1.4 if jna.jar is present in the libs?
Thanks for your time.
Regards,
Ananth
Re: Regarding Row Cache configuration and non-heap memory
Posted by aaron morton <aa...@thelastpickle.com>.
> In short the question is whether the row_cache_size_in_mb can exceed the heap setting for cassandra 1.1.4 if jna.jar is present in the libs?
Yes.
AFAIK jna.jar is not required for off heap row cache in 1.1.X
> My heap settings are 8G and new heap size is 1600M.
You can reduce the size of the heap in 1.1X. The default settings max out of 4G.
Cheers
-----------------
Aaron Morton
Freelance Developer
@aaronmorton
http://www.thelastpickle.com
On 4/10/2012, at 3:21 PM, Ananth Gundabattula <ag...@gmail.com> wrote:
> Hello,
>
> I have configured cassandra 1.1.4 to use row cache of 10GB ( the RAM on the machine is pretty big and hence the row cache size is high). My heap settings are 8G and new heap size is 1600M.
>
> As I read from the forum and documentation, jna.jar allows to use non-heap memory for the row caches.
>
> The question I have is how is the configuration in cassandra.yaml for row_cache_size_in_mb interpreted? Is it referring to the non-heap setting or the memory used inside the heap to maintain book-keeping information about the non-heap memory ( as I gather from the postings that heap is indeed used to some extent while still using the non-heap memory for row caches).
>
> In short the question is whether the row_cache_size_in_mb can exceed the heap setting for cassandra 1.1.4 if jna.jar is present in the libs?
>
> Thanks for your time.
>
> Regards,
> Ananth