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From Steve Loughran <ste...@apache.org>
Subject Re: Virtualization vs. Cassandra and Hadloop
Date Sat, 08 May 2010 07:40:13 GMT
Vijay wrote:
> Probably only me... but we have seen a higher latencies when using VMWare,
> also i think it depends on the H/W and VM configuration.... I have to figure
> out why (You might also try to mix the application's which runs on the
> hw).... i think there are people who run it on Amazons EC.

IO latency to virtual HDDs sucks as there is an extra layer there; the 
virtual OS thinks the blocks are laid out sequentially, but on the real 
disk they could be fragmented. Virtualised network IO can be slower too.

CPU, raw computation, can be fairly close to physicial.

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