[PETSC #17608] Re: general question on speed using quad core Xeons

[Satish Balay]

On Mon, 21 Apr 2008, Satish Balay wrote:

> For eg - On intel Xeon machine with DDR2-800 - you have [othe memory bus side]:
> bandwidth = 2(banks)* 2(ddr)* 8(bytes bus) * 800 MHz/sec *  = 25.6GByte/sec

My math was incorrect here..

DDR2-800 = 6.4Gb/s [its 2(ddr)* 400MHz/sec * 8bytes ]
So this machine has 4 memory banks. i.e the above is:

> bandwidth = 4(banks)* 2(ddr)* 400 MHz/sec* 8(bytes bus)  *  = 25.6GByte/sec


Satish