Do you have that observed yourself with a recent HBase (0.94 or later, which allocate heap for the memstore in 2mb chunks)?
Of course it's possible that there is a scenario that benefits from a larger eden size, I just haven't seen it.

 From: Azuryy Yu <[EMAIL PROTECTED]>
Sent: Wednesday, April 23, 2014 7:11 PM
Subject: Re: is my hbase cluster overloaded?

I cannot agree with you. I don't think memstore use the old gen, instead, for a heavy write cluster, memstore is keeping for a short time then flushed to the disk, so if you specifiedĀ  small Eden, there will be lots of promotions, and easy to cause FullGC.

so for the caseĀ in this thread, it's a heavy write cluster, so Eden should be large and MTT is also little large to avoid promotion.
On Wed, Apr 23, 2014 at 12:42 PM, lars hofhansl <[EMAIL PROTECTED]> wrote:

What makes you say this?
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