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From Ryan Rawson <ryano...@gmail.com>
Subject Re: heapSize() implementation of KeyValue
Date Mon, 01 Aug 2011 05:07:36 GMT
Each array is really a pointer to an array (hence the references),
then we are taking account of the overhead of the 'bytes' array
itself.

And I see 3 integers pasted in, so things are looking good to me....

On Sun, Jul 31, 2011 at 10:01 PM, Akash Ashok <thehellmaker@gmail.com> wrote:
> Hi,
>     I was going thru the heapSize() method in the class KeyValue and i
> couldn't seem to understand a few things which are in bold below
>
>
>  private byte [] bytes = null;
>  private int offset = 0;
>  private int length = 0;
>  private int keyLength = 0;
>
>  // the row cached
>  private byte [] rowCache = null;
>
>  // default value is 0, aka DNC
>  private long memstoreTS = 0;
>  * @return Timestamp
>  */
>  private long timestampCache = -1;
>
>
>  public long heapSize() {
>    return ClassSize.align(
>    // Fixed Object size
>    ClassSize.OBJECT +
>
> *    // Why this ?????
>    (2 * ClassSize.REFERENCE) +*
>
>    // bytes Array
>    ClassSize.align(ClassSize.ARRAY) +
>
>    //Size of int length
>    ClassSize.align(length) +
>
> *    // Why this ?? There are only 2 ints leaving length which are int (
> offset, length)
>    (3 * Bytes.SIZEOF_INT) +
> *
>    // rowCache byte array
>        ClassSize.align(ClassSize.ARRAY) +
>
>    // Accounts for the longs memstoreTS and timestampCache
>    (2 * Bytes.SIZEOF_LONG));
>  }
>

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