[Beowulf] VMC - Virtual Machine Console
Peter Skomoroch
peter.skomoroch at gmail.com
Fri Mar 7 09:05:03 PST 2008
Joe, thanks for the feedback. The bonnie results were not actually mine, I
was just pointing to some numbers run by Paul Moen.
Your 1GB file data is likely more representative, but with 15 GB ram,
> you need to be testing 30-60 GB files.
>
I'll try to tweak the BPS bonnie tests to run some large files...
On Fri, Mar 7, 2008 at 11:57 AM, Joe Landman <
landman at scalableinformatics.com> wrote:
> Peter Skomoroch wrote:
>
> > Extra Large Instance:
> >
> > 15 GB memory
> > 8 EC2 Compute Units (4 virtual cores with 2 EC2 Compute Units
> each)
> > 1,690 GB instance storage (4 x 420 GB plus 10 GB root partition)
> > 64-bit platform
> > I/O Performance: High
>
> Note: minor criticism, but overall, nice results.
>
> Looking over your bonnie results is worth a quick comment. Any time you
> have bonnie or IOzone (or other IO benchmarks) which are testing file
> sizes less than ram size, you are not actually measuring disk IO. This
> is cache speed pure and simple. Either page/buffer cache, or RAID
> cache, or whatever.
>
> We have had people tell us to our face that their 2GB file results (on a
> 16 GB RAM machine) were somehow indicative of real file performance,
> when, if they walked over to the units they were testing, they would
> have noticed the HD lights simply not blinking ... Yeah, an amusing
> beer story (the longer version of it), but a problem none-the-less.
>
> Your 1GB file data is likely more representative, but with 15 GB ram,
> you need to be testing 30-60 GB files.
>
> Not trying to be a marketing guy here or anything like that ... we test
> our JackRabbit units with 80GB to 1.3TB sized files. We see (sustained)
> 750 MB/s - 1.3 GB/s in these tests. We also note some serious issues
> with the linux buffer cache and multiple RAID controllers (buffer cache
> appears to serialize access). We do this as we actually want to measure
> disk performance, and not buffer cache performance.
>
> That criticism aside, nice results. It shows what a "cloud" can do.
>
> > Price: $0.80 per instance hour
>
>
> --
> Joseph Landman, Ph.D
> Founder and CEO
> Scalable Informatics LLC,
> email: landman at scalableinformatics.com
> web : http://www.scalableinformatics.com
> http://jackrabbit.scalableinformatics.com
> phone: +1 734 786 8423
> fax : +1 866 888 3112
> cell : +1 734 612 4615
>
--
Peter N. Skomoroch
peter.skomoroch at gmail.com
http://www.datawrangling.com
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://www.beowulf.org/pipermail/beowulf/attachments/20080307/a043bfa0/attachment.html>
More information about the Beowulf
mailing list