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User: jharel

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  1. Re:Andy Grove was not one of the cofounders. on Intel Co-Founder Calls For Tax On Offshored Labor · · Score: 1

    Correction- Wikipedia said he was employee number 3. He's still not a co-founder, however.

  2. Andy Grove was not one of the cofounders. on Intel Co-Founder Calls For Tax On Offshored Labor · · Score: 1

    Intel was founded by Gordon Moore and Robert Noyce. I think Andy Grove was employee number 5.

  3. The argument defeats itself on VIA Nano CPU Benchmarked, Beats Intel Atom · · Score: 1

    Since the "normal workload for an ultra-portable" isn't that much anyhow like you've said, then the performance difference is moot because it's not that big of a gap anyways. ...and by the same token, who in the world is going to use "ultra-portable" as "desktop replacement"? Pbbt.

  4. Re:Internet telephone game run amok, Slashdot help on Larrabee Based On a Bundle of Old Pentium Chips · · Score: 1

    Germany is a long way from Santa Clara. The fact remains that the original poster typed "Pat Gelsinger recently revealed that Larrabee's 32 IA cores will in fact be based..." instead of "Speculations are that..." I see the thread as "extreme sloppy reporting and non-checking by all parties" followed by "a massive episode of base-jumping related lemming deaths".

  5. Internet telephone game run amok, Slashdot helping on Larrabee Based On a Bundle of Old Pentium Chips · · Score: 5, Informative
    Hmm... Let's see where they got this from. They claim they got it from a Babelfish translation of Heise, a German site (Yeah, start wincing now...)

    http://babelfish.yahoo.com/translate_url?doit=done&tt=url&intl=1&fr=bf-home&trurl=http%3A%2F%2Fwww.heise.de%2Fct%2F08%2F15%2F022%2F&lp=de_en&btnTrUrl=Translate

    Actually, they got the "Gelsinger said so" remark from Expreview, itself a Chinese site:

    http://en.expreview.com/2008/07/07/larrabee-unleashes-2-tflops-capacity (note they curteously attached the Larrabee board diagram leaked from a while back):

    "Gelsinger said the Larrabee will be a 45nm product featuring SIMD technique, 64-bit address. Besides, 32 of cores runing at 2.00 GHz will unleash 2 TFLOPS capacity, twice as much as the RV770XT."

    But did Gelsinger really SAID those things?

    Here is the Google translation of the same Heise article: http://translate.google.com/translate?u=http%3A%2F%2Fwww.heise.de%2Fct%2F08%2F15%2F022%2F&hl=en&ie=UTF8&sl=de&tl=en

    It seems that no matter which crappily translated version of the German article one looks at, it appears that Gelsinger said no such thing... The part about Larrabee containing P54C cores was clearly in a separate paragraph, written after a speculative question.

    So I guess Expreview THOUGHT Pat said something after it took a too-short of a look at the Heise article, after which CustomPC sensationalized the whole thing, not really bothering to actually read even the translated link it posted. Now, some random Slashdotter is doing the same curtesy.

    There you go, folks- Internet reporting.

  6. Darwinism is stupid on Further Details From Soyuz Mishap · · Score: 1

    There is no "Soyuz Capsule Culture" that is trying to introduce a "new space hardware culture change", and there's no resistance to this non-existent "Soyuz Capsule Culture".

  7. Elsie Wahlig on erratum 298 on Erratum Plagues Quad-Core Opterons, Phenoms · · Score: 1
    AMD fellow Elsie Wahlig posted the following on a Linux mailing list:

    AMD Family 10h revision B2 processors suffer from an issue in the processor TLB known as erratum 298. Erratum 298 is documented in a forthcoming update to the Revision Guide for AMD Family 10h Processors (PID 41322). The workaround in the Revision Guide document is intended to be applied by BIOS. The BIOS workaround has performance implications which can be avoided by having the OS directly workaround the issue. A Linux 64-bit patch was developed for 2.6.23.8 by AMD's OSRC team and will be posted to this list by Joerg Roedel. The patch is for demonstration purposes and is NOT being recommended to be applied upstream.

    Erratum 298 will be described as follows: "The processor operation to change the accessed or dirty bits of a page translation table entry in the L2 from 0b to 1b may not be atomic. A small window of time exists where other cached operations may cause the stale page translation table entry to be installed in the L3 before the modified copy is returned to the L2. In addition, if a probe for this cache line occurs during this window of time, the processor may not set the accessed or dirty bit and may corrupt data for an unrelated cached operation. The system may experience a machine check event reporting an L3 protocol error has occurred. In this case, the MC4 status register (MSR 0000_0410) will be equal to B2000000_000B0C0F or BA000000_000B0C0F. The MC4 address register (MSR 0000_0412) will be equal to 26h."

    The L2 Eviction Linux kernel performance patch re-enables the registers set for the BIOS workaround described in the Revision Guide document. It then prevents the processor from performing the operation that can trigger erratum 298. The patch works by emulating the Accessed and Dirty bits.

    The basis for the kernel patch solution depends on the root cause of the L2 eviction problem. The only exposure for the problem is when the TLB needs to set an A or D bit in a page table entry. If the TLB never needs to set an A or D bit, the bug cannot occur. By emulating the A and D bits with the help of the Present and Writable bits, the patch will ensure the real A and D bits are always preset. It works by forcing a page fault when the first access is made to a page with the emulated A bit not set, and when the first write access is made to a writable page with the emulated D bit not set. Emulated A and D bits are stored in bits generally available to the OS in the page table entry.

    Elsie Wahlig