New EC2 instance types

Clint Byrum clint at
Fri Mar 9 07:17:06 UTC 2012

Excerpts from Martin Pool's message of Thu Mar 08 16:48:58 -0800 2012:
> On 9 March 2012 07:29, Clint Byrum <clint at> wrote:
> >
> > With the big push for sub-second latency in web services, I think the
> > syscall latency is enough of a selling point for me to consider it a
> > big win for almost any workload that you might want to run on an m1.small.
> That is indeed an interesting paper.
> Just to be a bit pedantic, their measurement of syscall latency showed
> that 32-bit apps on a 64-bit kernel are slower than 64-bit apps on a
> 64-bit kernel.  But, that's not the same choice you would have when
> deploying to EC2.  If you use a 32-bit instance you will have a 32-bit
> kernel.  (But, it probably is still better.)

>From the article:

"You can now launch 64-bit operating systems on the Small and Medium
instance types."

I read that as you will be running a 64-bit kernel and userland, and
so I would assume that means you would be gaining the reduced syscall
latency seen in the micro-benchmarks. Whether that leads to real-world
measurable improvements will of course require more investigation.

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