Why Doesn't the Itanium Get the Respect It's Due?

happycorp wonders: "As in recent years the Itanium does well, easily beating x86 processors even at its low clockspeed (1.4Ghz). The supercomputer people are serious about benchmarking (no easily tricked microbenchmarks or reliance on closed-source commercial apps), so the discrepancy between the performance and perception of this chip is serious. With a single-CPU Itanium2 system at around $2000 their price is already reasonable, and the price would come down (and software would be ported) if the Itanium ever became a mass market chip. Having an affordable chip one step above a Xeon or Opteron in floating-point performance would not be such a bad thing for gaming enthusiasts (or 3D artists). So, the recent article on the Top 500 supercomputers list brings up a question I've been meaning to ask: Why do we see so many disparaging opinions of the Itanium processor (all those 'Itanic' jokes, etc.)?" "It seems computing enthusiasts' sentiment is set against this processor, and its likely that it's going to be abandoned sooner or later. We'll be paying for x86 compatibility indefinitely (recall the Xeon has roughly three times the number of transistors of the ppc970 for example; but we hardly get three times the performance).

These are a couple scores from the top 20, with the total gigaflops divided by the number of processors to obtain a per-processor speed:

rank processor ghz (gflops / #procs) speed #5 ppc970 2.2 (27910 / 4800) 5.81 #7 itanium2 1.4 (19940 / 4096) 4.86 #10 opteron 2.0 (15250 / 5000) 3.05 #20 xeon 3.06 (9819 / 2500) 3.92
Given this, consider what a 2 or 3 Ghz Itanium could do.

(fine print: I am not affiliated with the Itanium or the top500 list in any way)."

Comments

Itanium2

[Anonymous Coward]

I had to study the chip in one of my EE class. The technology in it is really really impressive. I love the memory architecture provisions!

Sure, it's cheap NOW.

[Proc6]

Probably because when it mattered a single CPU Itanic was more like $12,000 and not $2,000. After fucking up all their marketing and delivering strategies no one wants one anymore.

No good compilers for EPIC

[Anonymous Coward]

I may be entirely wrong, but I believe the dislike for the Itanium stems from the fact that you can't compile any decently optimized code for it. Apparently, even Intel can't create a good compiler/linker and toolkit for creating machine code that makes good use of EPIC. Even though the processor itself is more efficient and faster, the same thing compiled to machine code running side by side with an Opteron or any other x86-64 chip will see the x86 win. If somebody could come up with a decent compiler/linker that provided full EPIC optimizations, they would be bangin, but they don't have it so we don't use it.

the problem is those are well optimized benchmarks

[Surt]

The people who work on scientific applications take performance seriously. They put a lot of effort into optimization. The itanium architecture is hard to optimize for, and the compilers just aren't there yet for the general case. So you wind up with a disparity between the performance in scientific applications and general purpose applications.

Other reasons itanium can't compete:

1) Compare the performance of itanium with xeon/opteron in running native x86 code.

2) Compare the costs of building real end user systems.

3) Compare the availability of windows xp drivers.

It's a pain in the ass

[unsinged int]

to compile for Itanium. Speaking as a compiler researcher, Itanium is great for generating research papers because there are all sorts of things that you can do from a compiler perspective. The problem is, outside a research environment, someone has to implement a lot of the ideas in an Itanium compiler to make it useful. Unfortunately, most of the stuff in the Itanium research papers isn't easy to implement and most of what gets put into commercial compilers are the easily implementable ideas.

Re:It's a pain in the ass

[Jeffrey Baker]

Yeah, nice CPU, difficult for software authors. I read a paper recently wherein the authors managed to reduce L4 microkernel message passing (up to 8 bytes) to 36 clock cycles, which is far faster than any other platform. But this was done by hand, and the compiler blurted out a routine that required 508 cycles. The gulf between what you can really do with an Itanium, and what normal software writers can do with it, remains huge.

Re:Follow the herd!

[chrismcdirty]

I only ever called it the Itanic because one of my professors, who works (or worked) at Intel and researched the architecture very extensively to document it also called it the Itanic. According to him, it was basically what everyone else has been saying so far.. great idea, bad execution.

Re:Follow the herd!

[jarich]

Many people here only know what has been said on Slashdot about the Itanium. They've never used one.

I worked at a startup that was building a database ~70 gigs in size. It took 2 months to build said database. Lots and lots of very small lookups and inserts.

Memory was our bottleneck. More ram equals more speed. So we spent BIG bucks and bought a quad Itanium with 12 or 16 gigs of memory (I forget exactly how much it had).

The Itanium was slower than a dual X86 with 2 gigs of memory! And not just a little slower. We spent weeks trying to get the database optimized.

Why does no one respect the Itaniums? Intel made a slow chip. Then they released the sequel. I've already paid my dues on that line once. I'm not playing this round.

Re:No x86 Compat is the Achilles' Heel

[hackstraw]

I think the big problem is that it cannot run x86 software very quickly.

Yeah, that is why semi trailers don't get respect like Dodge Neons. They use diesel fuel instead of unleaded!

My point is that if your buying a 64bit system that is fast in order to run your old 32bit programs slowly. Wrong tool for the job.

I've got 65 Itanium processors downstairs. They are fast and reliable for high memory bandwidth floating point calculations, which is what we use them for. They may be a disappointment with running IE or Outlook, but for crunching numbers they are great. I have yet to of tried an Opteron but will in the next couple of weeks. From what I understand those too have become great at high memory bandwidth number crunching, but I'll wait for the numbers vs marketing speak. Now, Itaniums do suck in the power consumption and heat dissipation department.

Itaniums get such a bad rep here on Slashdot because its cool to do so. Itaniums are made by the "big guy", Intel. If they were made by AMD they would not get the same rap as they do.

The other big thing against the Itaniums is market need. A generic x86 that you can throw in the trash and replace for about $1k if there are any problems are sufficient for 99% of the servers out there. If not even preferred. Now, what other market would want a fast 64bit architecture with high memory bandwidth -- databases. Sun and Oracle fill this void. Well except for the fast and high memory bandwidth part, but Oracle+Sun is a proven combination with years of experience. Solaris does not run on Itaniums. Linux does (flawlessly), but even Oracle+Linux is not that widely adopted. I have no clue about Windows state on an Itanium. I see no real use to run Windows on an Itanium, but someone else might, but I doubt its very common.

Although Intel has some more to go with the low-voltage Itaniums because they are capped at 1.3GHz, but they are working on that. Also, Intel has dropped the price of these guys considerably. This too was an issue with Itaniums, but they have dropped by about 1/2 the price over the years.

IMHO, Intel should continue on the power management issues and price and market these chips more for number crunching. Their performance on the top500 site is impressive, but even if all of the top 500 computers used 4,000 Itanium processors each, that would only be 2,000,000 processors total, and a super computer that size is not purchased very frequently.

Hey, I work with Itaniums.

[dlapine]

I have a nice cluster with ~1800 Itanium II's. It's fast, the CPU's stable, and it runs on Linux. I have a lot of hands-on experience with it.

A couple of points that seem to have been missed when looking at why the itanium less widespread:

• each CPU is quite large, having a square surface area for the unit about 2" x 5" and it's about 2" high
• That area includes a voltage regulater and the passive cooling fans
• It doesn't include any of the necessary active cooling

If you add these physical factors to the points already made about heat, power and EFI bios, it's obvious to say that Itanium won't run in your mini-ATX destop or laptop. This isn't a slam on the design, as it was never designed to run in those form factors, but it's hard to see how any cpu today is going to have a wide use if it isn't available for dual use for destop and servers. Once you eliminate the desktop market, (and I'm going to lump the workstation market in with the servers) the number of places you can sell these processors drops considerably.

Once you start adding in the lack of Windows support for itanium, the strides that the 86_64 architechture has made in capability, and the low numbers of current adopters, it's not looking like Itanium will ever gain widespread acceptance.

Why It's Not For Me...

[Nom du Keyboard]

Having an affordable chip one step above a Xeon or Opteron in floating-point performance would not be such a bad thing for gaming enthusiasts (or 3D artists).

Why this chip is not for me are two reasons:

1: I'm not buying one before the software is ported to it -- and at a comparable price to its PC equivalent!
2: It may be a step above an Opteron for floating point, but is it still that step about a dual processor Opteron that I can buy today for less money than a mono-processor Itantium?

As for the "Itanic" jokes (all of which are way off-base, since heat output of any H.M.S. Itanic would melt any iceberg long before it could do any damage), blame The Register. I saw them use the term long before anyone else.