On Thursday 04 March 2004 10:22 pm, Örn Hansen wrote:

fredag 05 mars 2004 03:36 skrev BandiPat:

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Steven, If you are wanting better performance, actually doing two things at once, then go for a dual cpu motherboard. If you are just wanting speedups, then go for the Opteron/Athlon64 cpu. Hyperthreading was just another gimmick Intel tried to use for an already bad cpu, the Pentium IV.

Which brings me to the question, of how does Athlon64 perform. Is it worth upgrading to it, there are numerous different reports out there. =============

The Athlon64 is the lower cost version of the Opteron cpu. I don't remember what it is missing that the Opteron has, maybe someone that has done a bit more research can volunteer that information. I have not experienced the chip myself, but have spoken to a couple people that have and they seemed pleased. I believe there are a couple of folks on this list that have it. Lee -- --- KMail v1.6 --- SuSE Linux Pro v9.0 --- Registered Linux User #225206 On any other day, that might seem strange...

On Thu, 4 Mar 2004 21:37:43 -0700 "Richard Mixon (qwest)" wrote:

Did I lose anything? If so how can I recover?

Browse the cron rpm with mc and copy /etc/crontab to your system. Charles -- "A word to the wise: a credentials dicksize war is usually a bad idea on the net." (David Parsons in c.o.l.development.system, about coding in C.)

The 2004-03-04 at 21:37 -0700, Richard Mixon (qwest) wrote:

This was a recent install of SLES 8 for AMD64. I had made not crontab entries for root myself. I have configured Apache, email and so on.

Did I lose anything? If so how can I recover?

I don't know your version of suse, but customarily suse uses /etc/crontab, not root's crontab. You should have lost nothing. -- Cheers, Carlos Robinson

Philipp Thomas wrote:

BandiPat [Thu, 4 Mar 2004 23:07:54 -0500]:

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The Athlon64 is the lower cost version of the Opteron cpu. I don't remember what it is missing that the Opteron has, maybe someone that has done a bit more research can volunteer that information.

It's missing the second RAM channel and most of all it's missing two Hypertransport channels so it can't be used to build multiprocessor systems, not even dual ones.

Philipp

I'm sure I've seen dual Athlon 64 mobo's on sale and a friend and I have discussed watching the price drops on them, it could be they didn't make a distinction between Athlon64 and Opteron, caveat emptor perhaps? -- i.e you could buy one of those boards and 2 Athlon 64 CPU's and discover you have a spare CPU you can't use. My earlier mail got bounced ..... I'm expecting delivery of an Acer Aspire 1501LCe laptop tomorrow, Athlon64 3000+, 512M DDR333, 10/100/1000 Nic, CD RW/DVD etc. and I shall install gentoo 64-bit on the 40G drive and SuSE 64-bit on the spare 20G for comparison. All the comparisons I've seen so far have been between 32-bit operating systems on P4 vs Athlon64, but I'm interested only in 64-bit performance. Regards Sid. -- Sid Boyce .... Hamradio G3VBV and keen Flyer Linux Only Shop.

Trey Gruel wrote:

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I'm sure I've seen dual Athlon 64 mobo's on sale and a friend and I have discussed watching the price drops on them, it could be they didn't make a distinction between Athlon64 and Opteron, caveat emptor perhaps? -- i.e you could buy one of those boards and 2 Athlon 64 CPU's and discover you have a spare CPU you can't use.

nope. the athlon 64 uses a 764-pin connection to the motherboard while the athlon 64 fx and opteron use a 940-pin connection. pretty soon the athlon 64 fx will switch to a 939-pin so it won't require use of registered ram. those extra pins provide the second memory channel and extra hypertransport channels that philipp was talking about.

And to think that the first microprocessor (Intel 4004) used a 16 pin package!

-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 On Thursday 04 March 2004 09:36 pm, BandiPat wrote:

On Thursday 04 March 2004 04:38 pm, Steven T. Hatton wrote: ***************

Steven, If you are wanting better performance, actually doing two things at once, then go for a dual cpu motherboard. If you are just wanting speedups, then go for the Opteron/Athlon64 cpu. Hyperthreading was just another gimmick Intel tried to use for an already bad cpu, the Pentium IV.

Lee

AMD does hyperthreading as well. The difference is the AMD chip emulates three processors, whereas the Intel emulates two. I already have a Pentium chip with hyperthreading. It costs far more than the motherboard which can be had at less that $100 US. I just want to know if it is worth the hassle, and _risk_, of swapping it out. I'm interested in demonstrable metrics. I would more than likely go with a 64bit chip before I went to two processors. The inter-processor protocols, the physical parameters introduced by the finite propagation speed of electromagnetic impulses, and the need for software to support (external) SMP make it unattractive.

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On Friday 05 March 2004 07:27 am, Bruce Marshall wrote:

On Friday 05 March 2004 02:02 am, Steven T. Hatton wrote:

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I would more than likely go with a 64bit chip before I went to two processors. The inter-processor protocols, the physical parameters introduced by the finite propagation speed of electromagnetic impulses, and the need for software to support (external) SMP make it unattractive.

I have a P4 2.8 running quite nicely here with HT. Can we gin up some simple test to see what it does?

I think I have an answer for you and Lee is right. I wrote a simple looping program that would show the elapsed time for nnnn passes through the loop. Run by itself, a valid time would be 1.55 secs for one pass. Start up another copy of the same program, and the time for each became 2.9. Close enough to twice the time that it's obvious the HT is a sham. -- +----------------------------------------------------------------------------+ + Bruce S. Marshall bmarsh@bmarsh.com Bellaire, MI 03/05/04 07:55 + +----------------------------------------------------------------------------+ "Why are there Braille signs on drive-up ATM's?"

On Friday 05 March 2004 08:01 am, Anders Johansson wrote:

On Friday 05 March 2004 13.57, Bruce Marshall wrote:

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On Friday 05 March 2004 07:27 am, Bruce Marshall wrote:

...

On Friday 05 March 2004 02:02 am, Steven T. Hatton wrote:

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I would more than likely go with a 64bit chip before I went to two processors. The inter-processor protocols, the physical parameters introduced by the finite propagation speed of electromagnetic impulses, and the need for software to support (external) SMP make it unattractive.

I have a P4 2.8 running quite nicely here with HT. Can we gin up some simple test to see what it does?

I think I have an answer for you and Lee is right.

I wrote a simple looping program that would show the elapsed time for nnnn passes through the loop. Run by itself, a valid time would be 1.55 secs for one pass. Start up another copy of the same program, and the time for each became 2.9. Close enough to twice the time that it's obvious the HT is a sham.

I think you miss the point of HT. HT lets the CPU do other things while it would otherwise be idle, such as for external IO and data fetching. It's an idea to avoid pipeline stalls. In real world settings, most benchmarks show something like a 30% improvement in performance.

What exactly does your loop do, other than just loop that is?

No, I didn't miss that point..... It's true that in some instances two cpu's (even of 1/2 the power of one) can be a better deal, but not very often. However, comparing a 2.8 P4 without HT to a dual-cpu 1.4 setup (a fair comparison), there is one advantage: when there's only one task to perform, it gets a cpu of 2.8ghz instead of just 1.4ghz. For the money, the HT doesn't really have any disadvantages that I can see, it just doesn't have all the advantages of two P4 2.8's. (which would cost a lot more money) -- +----------------------------------------------------------------------------+ + Bruce S. Marshall bmarsh@bmarsh.com Bellaire, MI 03/05/04 08:08 + +----------------------------------------------------------------------------+ "The Information Highway: 500 channels and not a thing to watch."

On Friday 05 March 2004 08:06 am, Gerhard den Hollander wrote:

* Bruce Marshall (Fri, Mar 05, 2004 at 07:57:37AM -0500)

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...

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I would more than likely go with a 64bit chip before I went to two processors. The inter-processor protocols, the physical parameters introduced by the finite propagation speed of electromagnetic impulses, and the need for software to support (external) SMP make it unattractive.

I have a P4 2.8 running quite nicely here with HT. Can we gin up some simple test to see what it does?

I think I have an answer for you and Lee is right.

I wrote a simple looping program that would show the elapsed time for nnnn passes through the loop. Run by itself, a valid time would be 1.55 secs for one pass. Start up another copy of the same program, and the time for each became 2.9. Close enough to twice the time that it's obvious the HT is a sham.

``obvious that HT is a sham'' and that is based on one simple looping program.

It's good enough for me...

Please read up onw hat HT is, what it does and under which circumstances it can be benificial.

I think I know what it is doing...

Or give it a try on your machien, and check the performance of a bunch of common programs with and witout HT.

It *IS* on my machine.

Your mileage may indeed vary, but I've found that enabling HT indeed gives a slightly snappier experience, and certain programs (esp once that do a lot of floating point operations and that are multithread aware) will clearly benefit from having it on.

But given that HT these dayts comes for free (more or less) it's a cheap test to turn it on .

I can agree with all of your points.... see my later message. I've been dealing with multi-engine machines (mostly large IBM mainframes) for the past 43 years so I think I know a little about schedulers (I've written a few) and cpu usage and what works and what doesn't. HT can have some advantages.... just not as much as a dual-cpu setup. And since I am subscribed to the list, please don't copy me on your posts. -- +----------------------------------------------------------------------------+ + Bruce S. Marshall bmarsh@bmarsh.com Bellaire, MI 03/05/04 08:15 + +----------------------------------------------------------------------------+ "Money will say more in one moment than the most eloquent lover can in years."

-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 On Saturday 06 March 2004 10:07 pm, Philipp Thomas wrote:

"Steven T. Hatton" [Fri, 5 Mar 2004 02:02]:

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AMD does hyperthreading as well. The difference is the AMD chip emulates three processors, whereas the Intel emulates two.

It does definitely *not* do any Hyperthreading, believe me. Maybe you're confusing it with Hypertransport, but the latter is a high speed serial bus to connect processor and chips.

Philipp

I don't claim to be an expert, but the way it was explained to me is the Intel chip emulates two CPUs by maintaining two sets of context registers and switching between them. The AMD chip does the same thing with three sets of context registers. By maintaining multiple thread contexts the chip can switch between threads without context switching delays. STH -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.2.2 (GNU/Linux) iD8DBQFASrDRwX61+IL0QsMRAi8KAJoDp9hQoh/23jbEZPyv3MKNJCNWdgCgjghn dK03NAjt44XN/PztsE0g+nY= =OHNJ -----END PGP SIGNATURE-----

-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 On Sunday 07 March 2004 06:59 am, Philipp Thomas wrote:

"Steven T. Hatton" [7 Mar 2004 00:19:06]:

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The AMD chip does the same thing with three sets of context registers.

Which AMD chip are we talking out? Non of the current AMD64 chips does have that feature. If they'd do, you'd see much more marketing blurb about it.

Philipp

I'll have to agree with you. And I don't recall the line of chips in question. I tried to find more information on the topic, and didn't see any indication that AMD is selling a simultaneous multi-threading chip. STH -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.2.2 (GNU/Linux) iD8DBQFASxE5wX61+IL0QsMRAsmQAKDLpqn8H6A7BxHA+49Fw9gpgYOSdACeJ6e1 Uf7D0qqWhad/TNl3oBKpaV0= =975u -----END PGP SIGNATURE-----