AMD's "Thorton"... What's the point?

[Lonyo]

Originally posted by: Whitedog
None of the new P4's are being made with 256k cache are they? (I know, celery, but that doesn't count here) I don't think so... SO WHY THE FARFINUGLE is AMD still putting 256k cache in them? The Dolts! WHy don't they just call the 256k chips Durons.

They've already came out with the 512k chips, so they need to just abandon the idea the 256k L2 is acceptable!

DOWN WITH 256k!!!!!

P4's have 64kb L1 + 512kb L2 = 576kb
Athlons have 128kb + 256kb = 384kb
Barton 128kb + 512kb = 640kb

And the extra 256kb on the Barton doesn't do all that much (as results have shown) so why bother putting 512kb on when they're gonna be moving on to totally new processors soon.
For Intel is was worthwhile, but now, for AMD, the same isn't quite so true.

 

[MadRat]

Show us how to squeeze that extra cache out of Intel processors. You comparison of Intel and AMD caches is nonsensical.

 

[XBoxLPU]

Originally posted by: MadRat
Show us how to squeeze that extra cache out of Intel processors. You comparison of Intel and AMD caches is nonsensical.

Here

 

[Lord Evermore]

And...only 8KB L1 cache in a P4. Intel has never been big on L1 cache size. Of course, they only have a data L1 cache, no instruction cache as L1.

Oh, and of course, the first P4's only had 256KB L2 cache as well, even though the Athlon always had 256KB.

 

[MadRat]

Originally posted by: XBoxLPU

Originally posted by: MadRat
Show us how to squeeze that extra cache out of Intel processors. You comparison of Intel and AMD caches is nonsensical.

Here

It supports what I was saying about the size of the Intel and AMD cache comparisons. The Intel P4's main cache is the L2 cache while the L1 cache is a trace cache that supplements the L2 cache. The AMD caches are more traditional designs and act independently, and therefore they behave differently than the Intel design. AMD's main cache is the L1 cache.

 

[TROGDORdBURNINATOR]

He's right. Intel duplicates the L1 cache data into the L2 thereby removing that much L2 cache from available use while AMD does not. This means that an Athlon XP with 256K L2 cache and 128K L1 cache actually has 384K of usable cache.
A Pentium 4 Northwood on the other hand actually has slightly less than 512K due to L1 data being stored there.