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Posted to user@cassandra.apache.org by Jason Wee <pe...@gmail.com> on 2014/01/02 07:08:53 UTC
Re: offheap component
Solely by the Cassandra version. Are you asking about a particular
component not mentioned above?
Not exactly. From version to version, the component of cassandra may reside
on heap or off heap, so is there a way to determine which component in the
cassandra version that may reside on heap or off heap?
On Wed, Jan 1, 2014 at 1:25 AM, Tyler Hobbs <ty...@datastax.com> wrote:
>
> On Tue, Dec 31, 2013 at 7:35 AM, Jason Wee <pe...@gmail.com> wrote:
>
>>
>> In Cassandra 1.2 and later, the Bloom filter and compression offset map
>> that store this metadata reside off-heap, greatly increasing the capacity
>> per node of data that Cassandra can handle efficiently. In Cassandra 2.0,
>> the partition summary also resides off-heap.
>>
>> How do we determine if a cassandra component is on heap or offheap?
>>
>
> Solely by the Cassandra version. Are you asking about a particular
> component not mentioned above?
>
>
>>
>> By off-heap, it means that the object is stored *not* in the allocated
>> heap in jvm but in native memory?
>>
>
> That's correct.
>
>
> --
> Tyler Hobbs
> DataStax <http://datastax.com/>
>
Re: offheap component
Posted by Robert Coli <rc...@eventbrite.com>.
On Thu, Jan 9, 2014 at 5:02 PM, Aaron Morton <aa...@thelastpickle.com>wrote:
> Row cache has been off heap for a while, and the key cache is still on
> heap.
>
Usage of the "off heap" row cache has enough associated heap consumption
that I feel compelled to mention that the name "off heap" is slightly
misleading. Certainly it consumes less heap than the on-heap row cache, for
the same number of cached rows... :D
=Rob
Re: offheap component
Posted by Aaron Morton <aa...@thelastpickle.com>.
in 1.2 bloom filters and compression meta data were moved off heap. in 2.0 index samples were also taken off heap.
Row cache has been off heap for a while, and the key cache is still on heap.
Any other components you were interested in ?
The best reference will be the NEWS.txt file and the blog posts at datastax.
Cheers
-----------------
Aaron Morton
New Zealand
@aaronmorton
Co-Founder & Principal Consultant
Apache Cassandra Consulting
http://www.thelastpickle.com
On 2/01/2014, at 7:08 pm, Jason Wee <pe...@gmail.com> wrote:
> Solely by the Cassandra version. Are you asking about a particular component not mentioned above?
>
> Not exactly. From version to version, the component of cassandra may reside on heap or off heap, so is there a way to determine which component in the cassandra version that may reside on heap or off heap?
>
>
> On Wed, Jan 1, 2014 at 1:25 AM, Tyler Hobbs <ty...@datastax.com> wrote:
>
> On Tue, Dec 31, 2013 at 7:35 AM, Jason Wee <pe...@gmail.com> wrote:
>
> In Cassandra 1.2 and later, the Bloom filter and compression offset map that store this metadata reside off-heap, greatly increasing the capacity per node of data that Cassandra can handle efficiently. In Cassandra 2.0, the partition summary also resides off-heap.
>
> How do we determine if a cassandra component is on heap or offheap?
>
> Solely by the Cassandra version. Are you asking about a particular component not mentioned above?
>
>
> By off-heap, it means that the object is stored *not* in the allocated heap in jvm but in native memory?
>
> That's correct.
>
>
> --
> Tyler Hobbs
> DataStax
>