Dan,
The rule of thumb is that if you don't quadruple cache, don't bother. Taking P4 from 256K to 1 megabyte of cache would be expected to increase performance by 5%. Taking it to 512K would make a 2GHZ perform like a 2.05GHZ
OTOH, P4 crashes so hard when it encounters a stall, that it might be more sensitive to increases in cache size than most processors, so there may well be more of an improvement.
On a broad range of applications, you may be right, but lately, everything seems to be turning around performance in benchmarks, and I can think of a few that will see a dramatic impact.
One I can think of immediately is SETI@Home. I believe the work unit is about 300K, and it will just fly when run on Northwood processor. Expect to hear A LOT about SETI a few months from now.
But IMO, the real goal of the 512K L2 is to soak up extra fab capacity. Intel has a huge surplus of it, and if Intel can somehow force the mainstream .13u processor to be let's say 170 mm^2 rather than 100 mm^2, it will be a victory for Intel, since AMD's capacity will be capped, while Intel will get the rest of the market by default. That's what I would do.
Joe |
