[illumos-Discuss] CPU/Chipset architecture for high performance ZFS servers

[Alasdair Lumsden]

On 01/04/2011 14:16, Richard Elling wrote:
<snip>
> You won't run out of CPU, but you can run out of I/O.  For most 2-socket Intel boxes, there is
> only one IOH. The 5520 IOH only provides 36 PCI-e lanes, so you will see different combinations
> of PCI-e bridges on systems from various vendors. Obviously, fewer bridges is better and that tends
> to become the biggest architectural difference in the machines.  Similar analysis applies to the AMD
> chipsets.  For an interesting case of simplicity built for speed, look at the Sun X4500 design.

*nods*

There are also the memory speed differences, the latest AMD Opteron 6xxx 
series seems able to go all the way up to 256GB Ram at 1333MHz, whereas 
the Dell Intel Nehalem boxes appear to drop down to 800MHz for the RAM 
speed beyond 96GB. I'm not sure how this would impact the maximum 
throughput of the box though.