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From Stack <st...@duboce.net>
Subject Re: Size of KeyValue
Date Thu, 24 Nov 2011 04:41:59 GMT
On Wed, Nov 23, 2011 at 3:40 PM, lars hofhansl <lhofhansl@yahoo.com> wrote:
> Looking at KeyValue I see three variable purely used for caching:
> timestampCache(long), rowCache(byte[]), and keyLength(int).
> From a quick glance over the code I do not see many spots where we repeatedly get the
TS, rowKey, of keyLength from the same KV.
> Together these consume 24 bytes (almost 1/2 of KeyValue's constant memory overhead) on
every key value created, and we create
> a *lot* KVs (real and "fake" ones) during scanning and seeking.
> Were these added to address specific performance concerns? If not, we might consider
removing these.

IIRC, I added them after watching stuff in a profiler (a long time
ago).  Things change.  Thats a lot of static mem to give up.


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