Re: Intel EM64T vs. Opteron
On 14 Oct 2005, at 8:06 am, mike wrote: Basically, I'd be looking at an Intel 830D (3.0ghz, dual-core, EM64T) processor-based system, with 1 gig of ram and SATA HD vs. a single-core Opteron 1.8ghz (or a dual-processor NOT dual-core Opteron 1.8ghz) system, same HD and same RAM. Has anyone had the opportunity to benchmark this, or have any real experience with changing the underlying platform? Our experience with IBM HS20 blade servers shows the 2.4 GHz Opteron blows the 3.2 GHz EM64T out of the water on our bioinformatics codes, which are predominantly limited by integer performance and memory bandwidth. And uses a lot less power (this is significant when you have about 1000 processors in the cluster!). No more EM64T for us, at least for a while. One thing to be careful with, if it's a dual CPU opteron machine that you're benchmarking, is that you need a really up to date kernel that gets the NUMA topology right; our initial benchmarks were disappointing, and it turned out that the the numa topology stuff in the kernel was exactly backwards, so every process was always accessing memory local to the other CPU. This has been fixed in recent kernels. Tim -- To UNSUBSCRIBE, email to [EMAIL PROTECTED] with a subject of "unsubscribe". Trouble? Contact [EMAIL PROTECTED]
Re: Intel EM64T vs. Opteron
On Fri, Oct 14, 2005 at 01:59:16PM -0700, mike wrote: > The main question is 64-bit support using Debian-amd64/kernel 2.6.x > [on EM64T]. Is it any different than installing Debian-amd64 on an > Opteron box? In my experience, no, it's no different at all. Ignoring speed/whatever, running Sarge 64-bit Debian on our one (dual processor, hyperthreading) EM64T box has been no different than on the numerous Opteron boxes we run. I can't comment on the debian _kernels_, as we compile from upstream, but we've had no problems with the box. --Pete -- To UNSUBSCRIBE, email to [EMAIL PROTECTED] with a subject of "unsubscribe". Trouble? Contact [EMAIL PROTECTED]
Re: Intel EM64T vs. Opteron
On 10/14/05, Lennart Sorensen <[EMAIL PROTECTED]> wrote: > > Do you know what chipset/motherboard the p4 system would be using? > LGA775 socket E7230 chipset it appears - i think i saw another model or two that may have slightly different chipsets, but i can't find them now. anyway, from the discussions it sounds like Opterons are just a better choice for now, based on this and some other collateral and forum posts i've been able to google up.
Re: Intel EM64T vs. Opteron
On Fri, Oct 14, 2005 at 01:59:16PM -0700, mike wrote: > Please note the "I have a chance" line - I have some discounts that I > can apply against Intel 830D's which would take the overall cost down > to less than an Opteron machine - and I'd be getting dual-core for > that lower price as well. > > Pentium 4 830D's have EM64T support; it's not just Xeons. Well discounts are nice. > You can compare anything you want. It's a comparison for that reason. > My two options are an 830D or an Opteron-based system. The main > question is 64-bit support using Debian-amd64/kernel 2.6.x. Is it any > different than installing Debian-amd64 on an Opteron box? I already > run it on 7 Opteron-based systems and an Athlon64 system. Installing should be exactly the same as long as the chipset and such in the machine is supported in 2.6.8 kernel (or 2.6.12 if you use my version of the installer). > >From the replies after this, it sounds like the EM64T 64-bit arch is a > little slower than AMD64. However, maybe that's just a bottleneck that > will be fixed soon, much like when Hyperthreading came out? No, I don't think the current em64t design will ever run faster in 64bit than 32bit. The opteron/a64 was designed from scratch with 64bit in mind. The netburst architecture wasn't. It had to be modified to handle 64bit without a complete redesign from scratch. It is however from what I gather not a particularly noticeable difference, and if the program has any advantages from 64bit (like using sse for floating piint instead of x87) and using more than 4GB memory mapped, then it should be worth the slight drop in speed. Do you know what chipset/motherboard the p4 system would be using? Len Sorensen -- To UNSUBSCRIBE, email to [EMAIL PROTECTED] with a subject of "unsubscribe". Trouble? Contact [EMAIL PROTECTED]
Re: Intel EM64T vs. Opteron
On 10/14/05, Lennart Sorensen <[EMAIL PROTECTED]> wrote: > > I have a chance soon to switch out my servers, and going the Intel > > route I would be able to get a lot more bang for my buck. The website > > says that EM64T works fine with Debian-amd64, I just want to make sure > > there's no gotchas, compared to using it on an Opteron-based system. > > When did xeon servers become cheaper than opteron servers? :) > Please note the "I have a chance" line - I have some discounts that I can apply against Intel 830D's which would take the overall cost down to less than an Opteron machine - and I'd be getting dual-core for that lower price as well. Pentium 4 830D's have EM64T support; it's not just Xeons. > > Remember you can not compare an 830D to an opteron. That's like > comparing an 830D to a xeon. Rather unreasonable comparison. Compare > it to an Athlon 64 X2 system. > You can compare anything you want. It's a comparison for that reason. My two options are an 830D or an Opteron-based system. The main question is 64-bit support using Debian-amd64/kernel 2.6.x. Is it any different than installing Debian-amd64 on an Opteron box? I already run it on 7 Opteron-based systems and an Athlon64 system. >From the replies after this, it sounds like the EM64T 64-bit arch is a little slower than AMD64. However, maybe that's just a bottleneck that will be fixed soon, much like when Hyperthreading came out?
Re: Intel EM64T vs. Opteron
On Fri, Oct 14, 2005 at 11:58:56AM -0400, Karl Magdsick wrote: > Along the same lines, do the EMT64 chips still actually run slower in > 64-bit mode as compared to 32-bit mode? If the xeon em64t users on this list in the past are anything to go by, the answer is yes. Not usually much but a bit. Oposit of the amds in any case. Len Sorensen -- To UNSUBSCRIBE, email to [EMAIL PROTECTED] with a subject of "unsubscribe". Trouble? Contact [EMAIL PROTECTED]
Re: Intel EM64T vs. Opteron
On Fri, Oct 14, 2005 at 12:06:24AM -0700, mike wrote: > I recently (re-)subscribed to the mailing list, I have a couple > specific questions, and can't seem to find any good data about it, and > would like to tap people who probably have some real-world experience > with it. > > First off, I am a user of Debian-amd64 right now - and I love it. I > run it on Opterons. It screams. > > I have a chance soon to switch out my servers, and going the Intel > route I would be able to get a lot more bang for my buck. The website > says that EM64T works fine with Debian-amd64, I just want to make sure > there's no gotchas, compared to using it on an Opteron-based system. When did xeon servers become cheaper than opteron servers? :) > Basically, I'd be looking at an Intel 830D (3.0ghz, dual-core, EM64T) > processor-based system, with 1 gig of ram and SATA HD vs. a > single-core Opteron 1.8ghz (or a dual-processor NOT dual-core Opteron > 1.8ghz) system, same HD and same RAM. Has anyone had the opportunity > to benchmark this, or have any real experience with changing the > underlying platform? I can build an 830D based system with dual-cores > for cheaper than a single-core Opteron box right now (I have some > discounts) but if the performance isn't as good as it seems it should > be, or there's some odd things that must be done to get EM64T to work > properly under Debian-amd64, I'd like to know that before committing > to the hardware choice :) I know the athlon 64 is very fast and certainly faster than the p4 I have around here (at a much higreh clock rate). From what I have gathered reading this list, the P4/xeon slows down a little in general when you enable 64bit mode. AMDs speed up. Given the AMD is usually faster at mosts tasks already in 32 bit mode, the situation is not improved (for intel) in 64bit mode. Remember you can not compare an 830D to an opteron. That's like comparing an 830D to a xeon. Rather unreasonable comparison. Compare it to an Athlon 64 X2 system. > I plan on running the latest Linux kernel 2.6.x - two of my servers > will be LVS machines and I will have a handful of webservers running > this platform, in case you're wondering about specific usage. > > Thanks in advance for any feedback! To me the netburst architecture looked wrong when it came out. I still think it looks wrong and I will be happy when intel finally dumps it for the pentium-m based architecture in their server and desktop lineups. Until then I will buy what is the fastest (and cheapest) systems you can get, which is AMD based systems. Of course I haven't been buying dual core, which do seem rather pricey relate to single core. for example: Asus A8V Deluxe $132cdn AMD Athlon 64 X2 3800 $440cdn AMD Athlon 64 X2 4800 $1066cdn 2 x 512MB DDR400 $122cdn 2 x 1GB DDR400 $330cdn Total is $694cdn (3800 1GB) to $1528cdn (4800 2GB) Asus P5LD2 $153cdn Intel Pentium D 820 $314cdn (2.8GHz) Intel Pentium D 840 $670cdn (3.2GHz) (I am ignoring the extreme edition as being silly expensive) 2 x 512MB DDR2-533 $140cdn 2 x 1GB DDR2-533 $280cdn Total is $607cdn (D820 1GB) to $1103cdn (840D 2GB) Video, HD, case, etc should be similar between systems and hence not relevant. An X2 3800 = 2xAthlon64 3200 (which in my experience is easily faster than a 3.2GHz P4). An X2 4800 = 2xAthlon64 4000. The 4600 is the same but with half the cache. Given the more efficient memory interface of the athlon64 x2 than the shared FSB 830D, and that the 3800 is a dual of a cpu that already is as fast as the single core in the 840D, it is actually fair to compare the X2 3800 to the 840D (which costs more of course). The 820D and 830D might be cheaper, but they will also be slower for probably just any any task you throw at them. Enough ranting from me. :) Len Sorensen -- To UNSUBSCRIBE, email to [EMAIL PROTECTED] with a subject of "unsubscribe". Trouble? Contact [EMAIL PROTECTED]
Re: Intel EM64T vs. Opteron
Along the same lines, do the EMT64 chips still actually run slower in 64-bit mode as compared to 32-bit mode? -Karl
Re: Intel EM64T vs. Opteron
On 00:06 Fri 14 Oct , mike wrote: > Hi all, > > I recently (re-)subscribed to the mailing list, I have a couple > specific questions, and can't seem to find any good data about it, and > would like to tap people who probably have some real-world experience > with it. > > First off, I am a user of Debian-amd64 right now - and I love it. I > run it on Opterons. It screams. > > I have a chance soon to switch out my servers, and going the Intel > route I would be able to get a lot more bang for my buck. The website > says that EM64T works fine with Debian-amd64, I just want to make sure > there's no gotchas, compared to using it on an Opteron-based system. > > Basically, I'd be looking at an Intel 830D (3.0ghz, dual-core, EM64T) > processor-based system, with 1 gig of ram and SATA HD vs. a > single-core Opteron 1.8ghz (or a dual-processor NOT dual-core Opteron > 1.8ghz) system, same HD and same RAM. Has anyone had the opportunity > to benchmark this, or have any real experience with changing the > underlying platform? I can build an 830D based system with dual-cores > for cheaper than a single-core Opteron box right now (I have some > discounts) but if the performance isn't as good as it seems it should > be, or there's some odd things that must be done to get EM64T to work > properly under Debian-amd64, I'd like to know that before committing > to the hardware choice :) Just a heads up about the big drop in Opteron pricing: http://www.theinquirer.net/?article=26927 -- To UNSUBSCRIBE, email to [EMAIL PROTECTED] with a subject of "unsubscribe". Trouble? Contact [EMAIL PROTECTED]
Intel EM64T vs. Opteron
Hi all, I recently (re-)subscribed to the mailing list, I have a couple specific questions, and can't seem to find any good data about it, and would like to tap people who probably have some real-world experience with it. First off, I am a user of Debian-amd64 right now - and I love it. I run it on Opterons. It screams. I have a chance soon to switch out my servers, and going the Intel route I would be able to get a lot more bang for my buck. The website says that EM64T works fine with Debian-amd64, I just want to make sure there's no gotchas, compared to using it on an Opteron-based system. Basically, I'd be looking at an Intel 830D (3.0ghz, dual-core, EM64T) processor-based system, with 1 gig of ram and SATA HD vs. a single-core Opteron 1.8ghz (or a dual-processor NOT dual-core Opteron 1.8ghz) system, same HD and same RAM. Has anyone had the opportunity to benchmark this, or have any real experience with changing the underlying platform? I can build an 830D based system with dual-cores for cheaper than a single-core Opteron box right now (I have some discounts) but if the performance isn't as good as it seems it should be, or there's some odd things that must be done to get EM64T to work properly under Debian-amd64, I'd like to know that before committing to the hardware choice :) I plan on running the latest Linux kernel 2.6.x - two of my servers will be LVS machines and I will have a handful of webservers running this platform, in case you're wondering about specific usage. Thanks in advance for any feedback! - mike
