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From Jukka Zitting <jukka.zitt...@gmail.com>
Subject Re: Using DirectMemory as second level cache
Date Mon, 08 Jul 2013 11:18:55 GMT
Hi,

On Mon, Jul 8, 2013 at 1:54 PM, Chetan Mehrotra
<chetan.mehrotra@gmail.com> wrote:
> Initial test based on this show quite a bit of saving in terms of
> memory taken

This suggests that we could/should also look at optimizing the size of
objects cached in the JVM heap. Your numbers suggest that each
Document cache entry takes a few kilobytes of memory on average, which
is quite a lot. The average SegmentMK entry is an order of magnitude
smaller.

> Thoughts?

In general I think such an L2 cache makes a lot of sense (TarMK uses
memory mapped files for the same effect). That said, I think we should
also pay attention to how the L1 cache could be used more effectively
and not just let an L2 cache postpone the issue to a bigger scale.

BR,

Jukka Zitting

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