Cache Locking on Pentium Processor Family?

[arintel1]

Hi everybody,

I'm Arintel. I'm new to this forum.

I'm looking for a document on how to implement Cache Locking (including data & instruction cache locking and code sample) on Pentium Processor Family.

It should be similar to the documents I found below, which are for CPU 80321 and XScale micro-architecture:

http://www.intel.com/design/iio/papers/27387202.pdf
(section 4.5 and appendix C)

http://www.intel.com/design/intelxscale/27347302.pdf
(section 6.4 and its examples)

Can someone tell me how to get it or where to buy it?
Can I possibly find it in Early Access to Intel Platforms Program ?

Thanks sincerely,
ARINTEL

[Vladimir_Dudnik]

HI, I recimmend you to take a look on

http://developer.intel.com/design/pentium4/manuals/index_new.htm (document number 248966).

Regards,
Vladimir

[arintel1]

Hello vdudnik,

Thanks for your reply.

I have skimmed through all IA-32 manuals before but I found no detailed discussion of Cache Locking. Or did I miss something?

I expect something very similar to the sections in the documents that I mentioned.

Regards,
ARINTEL

[Vladimir_Dudnik]

Hi,

I'm sorry, that's right. Intel Pentium family processors do not support cache locking feature.

Regards,

Vladimir

[arintel1]

Hello Vladimir,

Are you sure Intel Pentium family processors do not support cache locking feature? Or are the documents confidential?

If they do not support cache locking, is there any way to ensure high stability in execution time on those CPUs?


Thanks a lot,
ARINTEL

[Vladimir_Dudnik]

Hi Arintel,

as far as I know, IA32 processors do not support cache locking, that's only feature of Xscale processors. So, there is no way to ensure that data will be locked in cache.

BTW, Happy New Year, why you are online at 31 Dec:)

Vladimir

[arintel1]

Hi Vladimir,

Happy New Year. :)

Do you know how to ensure high stability in execution time on IA-32 processors?

Thanks a lot
ARINTEL
P.S. I'm always online. :)

[Vladimir_Dudnik]

I'm recommend you to read Intel Pentium 4 Software Developer's Manual and IA32 Software Optimization Guide. There is some hints how to arrange memory accesses to take advantages of hardware prefetching mechanism in available Intel Pentium 4 processors and to achieve better performance.

Vladimir

[arintel1]

Hi Vladimir,

Would you look into this document?
http://faculty.cs.tamu.edu/bettati/Courses/663/Fall-2004/Slides/DataCachesMultitasking.pdf

On page 2 it says "Cache locking is available in ...., Intel x86, ..."

Intel x86 is one of IA-32 processors, right?

ARINTEL

[Vladimir_Dudnik]

M-m-m, I read about something similar in Pentium 4 Dev Guide, that's available only for special processor's states, with special memory pages attribute. In other words, it is unavailabe under Windows OS. You definetely need to study processors manual to take advantage of this feature (if it is possible) for your own hw board design.

Vladimir

[arintel1]

Hi Vladimir,

Could you please give me the link to the particular document and section that discuss about those special processor's states?

Thanks sincerely,
ARINTEL

[Vladimir_Dudnik]

Hi,

As I mentioned you before, my recomendation is to read IA-32 Intel Architecture Software Developer's Manual (it is the most complete source of Intel 32-bit Architecture features), and in particularly, please take a look on Volume 3: System Programming Guide, Chapter 10 - Memory Cache Control. Article 10.5.3 Preventing Caching describes how to disable caching.

Regards,

Vladimir