[Beowulf] Has anyone actually seen/used a cell system?

[Andrew Shewmaker]

On 10/1/06, Andrew Shewmaker <agshew at gmail.com> wrote:

> It looks like a preproduction 2.4 GHz Cell is 2-6 times faster than a 2.93 GHz
> Core2 at SGEMM.  That's an awfully big range, so hopefully someone
> wil be kind enough to benchmark libgoto on Core2 for us.  The history file
> indicates that libgoto is optimized for Core2, but I don't have one to test.

I apologize for replying to my own message, but the 2-6 times faster isn't a
good range since it assumes only one of the Core2 cores is used for the
upper bound (80/12.5).  Assuming that ScienceMark's BLAS scaled
perfectly across two cores, the upper bound would be about 3.

So, it looks like a preproduction 2.4 GHz Cell is about 2-3 times faster than a
2.93 GHz Core2 at SGEMM.

However, IBM intends to scale production Cells to 3.2 GHz (let's assume a
1.3x speedup).  And Intel intends to double their cores again, and we expect
them to lower the clock of those cores too.  Anandtech thinks 2.66GHz
is the fastest we'll see.

http://www.anandtech.com/mac/showdoc.aspx?i=2832&p=6

So, that might give us a 2.66/2.93*2 = 1.8x speedup for SGEMM on Intel's quad
core.  The Cell may only be 1.4-2.3 faster at SGEMM than an Intel solution by
Q107.  Most people I know would love to have that kind of speedup if it didn't
take too much effort.  Sequoia looks like it might make the level of effort
reasonable.

FYI, Charm++ is also working on the difficulty of Cell programming.

http://charm.cs.uiuc.edu/posters/CellProcessor.pdf

-- 
Andrew Shewmaker