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InfiniBand Drivers Released for Xserve G5 Clusters
A user writes, "A company called Small Tree just announced the release of InfiniBand drivers for the Mac, for more supercomputing speed. People have already been making supercomputer clusters for the Mac, including Virginia Tech's third-fastest supercomputer in the world, but InfiniBand is supposed to make the latency drop. A lot. Voltaire also makes some sort of Apple InfiniBand products, though it's not clear whether they make the drivers or hardware."
The article is still subscriber-only, but Linux Weekly News has a good summary of some discussion on the LKML about InfiniBand. Greg K-H's original posting can be found here. Basically, he feels that it's impossible to implement the specification for InfiniBand in a free/open source product without violating the licensing agreement of the spec, because of patent infringement.
installing Infiniband on a single unit G5....
With so few companies left doing anything Infiniband related, makes you wonder what the thinking is here.
http://www.oreillynet.com/pub/a/network/2002/02/04 /windows.html
This is a short into to infiband.
"InfiniBand breaks through the bandwidth and fanout limitations of the PCI bus by migrating from the traditional shared bus architecture into a switched fabric architecture."
"Each connection between nodes, switches, and routers is a point-to-point, serial connection. This basic difference brings about a number of benefits:
Because it is a serial connection, it only requires four as opposed to the wide parallel connection of the PCI bus.
The point-to-point nature of the connection provides the full capacity of the connection to the two endpoints because the link is dedicated to the two endpoints. This eliminates the contention for the bus as well as the resulting delays that emerge under heavy loading conditions in the shared bus architecture.
The InfiniBand channel is designed for connections between hosts and I/O devices within a Data Center. Due to the well defined, relatively short length of the connections, much higher bandwidth can be achieved than in cases where much longer lengths may be needed."
"The InfiniBand specification defines the raw bandwidth of the base 1x connection at 2.5Gb per second. It then specifies two additional bandwidths, referred to as 4x and 12x, as multipliers of the base link rate. At the time that I am writing this, there are already 1x and 4x adapters available in the market. So, the InfiniBand will be able to achieve must higher data transfer rates than is physically possible with the shared bus architecture without the fan-out limitations of the later."
This is cool. The Xserve is a great server. We got one at work and we used it as a mirror for a while before switchover. This thing never crashes. according to one of the articles these drivers will optimize the power of these beasts...
I've always understood that Myrinet is one of the better latency products available.
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And it has MacOSX Drivers:
http://www.myri.com/scs/macosx-gm2.html
Myrinet is used by 39% of the Top500 list published in November 2003
http://www.force10networks.com/applications/roe.a
The Virginia Tech cluster isn't on the top 500 list anymore:
from http://www.top500.org/lists/2004/06/trends.php
* The 'SuperMac' at Virginia Tech, which made a very impressive debut 6 month ago is off the list. At least temporarily. VT is replacing hardware and the new hardware was not in place for this TOP500 list.
People have already been making supercomputer clusters for the Mac, including Virginia Tech's third-fastest supercomputer in the world, but InfiniBand is supposed to make the latency drop.
Note that V.T.'s cluster already uses InfiniBand, courtesy of Mellanox.
It's mentioned at V.T.'s pages.
...Halo and UT2004 were starting to slow down on my 1200 CPU cluster!
"Microsoft killed my company, I hold a personal grudge. I don't use Microsoft products and neither should you."-JWZ
The BigMac at VA Tech missed the list this year because they were busy switching over to DP G5 Xserves. Last I heard, they had completed the project and were busy re-benchmarking the beast. I I also heard that it was poised to move to number 2 possibly on the list after it was retested officially. The Army's version of the BigMac will probably take that title away though. That then 2 of the top 3 machines will be G5 based. Too Cool!
Why doesn't anything interesting happen when I have mod points?
No offense, but you don't know what you're talking about. IB can sustain tranfer rates of 700 MB/s; the best I've ever seen from GigE was almost an order of magnitude lower, not to mention the two orders of magnitude drop in latency with IB. That might not mean much to you, but I guarantee you it's a big deal for folks with big parallel scientific codes.
Oh, and your pricing's wrong too. In the quantities you'd need it for a decent size cluster, IB gear is about the same cost as its direct competitors (Myrinet and Quadrics).
Doubtful. IBM's BlueGene is the king right now(well for the time being), but I don't see Big Mac(either version) beating the earth sim. Still, 2 out of the top 4 isn't bad.
Monstar L
Back in 2002, people were pitching IB as a replacement for PCI. Today, nobody tries to do that -- IB and PCI are used for different purposes (clustering and I/O expansion, respectively).
Small Tree also makes cool multiport gigabit ethernet cards that support 802.1ad bonding. Really, the gigE cards are the more interesting thing for most of us who don't have a supercomputing cluster to run. The two-port version is less than $300. They work on Linux as well.
http://small-tree.com/mp_cards.htm
Gigabit has a latency of about 100 microseconds and realistic throughput of about 50MB/s. Infiniband has a latency of about 15 microseconds and a throughput of about 500MB/s.
I mostly sell small Apple workgroup clusters of 16 nodes, and these are almost always just a gigE backbone. There are certain classes of problems that can benefit from Infiniband at low node counts, but for the most common apps, like gene searching using BLAST, gigE is just fine.
- "When you want something with all your heart, the entire universe conspires to give it to you" -Paulo Coelho
October 14, 2004 Pg. 54
http://www.netlib.org/benchmark/performance.pdf
http://appleturns.com/scene/?id=4980
"Calm down, Beavis; take a closer look at the third and fourth entries and you'll realize that they're the same exact cluster, before and after its owners added another 64 processors to it. In much the same way, System X is also listed in the seventh, ninth, and eleventh slots, with scores taken at various points along its journey to life as a complete 1,100-Xserve system. Factor out the doubles and, barring an "October Surprise," System X ought to sit in fifth place, under an Alpha cluster, a new Itanium2 system, the once-mighty Earth Simulator, and the new top dog, that chunk of IBM's unfinished BlueGene. Woo-hoo, PowerPCs in two of the top five! No other chip can say that."
~hylas
Yes, Twelve Captures Fifth (10/14/04).
an one program them in Python or Perl, or only "Real Programmers(tm)" languages like Java and C++?
They can be programmed in any language. Fortran and C are by far the most common choices. It's common to see perl and shell scripts used as glue between standalone modular programs. It's about the only place where you'll still occasionally find hand assembly in the inner loops, though that's becoming less common as more compilers support MMX,SSE, etc instructions.
You won't find a lot of interpreted languages doing heavy lifting in HPC. While a typical server is I/O bound (disk or net) and so can spare CPU cycles on an interpreted language, in HPC the CPU is normally pegged.
This is the Apple section of slashdot. These sections are present for a reason. Apple policies wern't being discussed at all, but Infiniband policies. Given that drivers are now released for Infiniband for OSX, the question of what this brings to Apple Clusters is something relevant to be discussed here. The reason I would brand you a troll is that you're speaking negatatively about something that is not relevant to this section of /.: How linux clusters are effected by IP issues decided by Infinband. You have yet to frame this in terms of contrasting how their policies effect Linux and how Apple drivers are now released. If you had started that way, then perhaps I would have just watched the discussion.
/. at the appropriate time (when the content on LWN becomes publically available). I all but wrote the submission for you! That hardly sounds like I'm trying to keep you from discussing this at all. I've suggested broadening your audience even.
To say I don't want to hear what you have to say has been already been proven wrong, as I have suggested previously that you make such a discussion in the appropriate section of
Also to say I've made up my mind about Infiniband or Linux v. Apple clusters couldn't be further from the truth. I haven't said anything about what I prefer, what is best, or anything to indicate my opinion. In fact, I have no informed opinion on the subject at all, much less have I expressed one. As a matter of fact, what is my direct put down of Linux-based clusters? Any comment I made was that this is that clusters likely to look at Infiband are not small scale, hobbyist clusters, but more likely larger clusters with larger budgets, so if the specs are free or not will be less of a factor.
I am, and always will be, an idiot. Karma: Coma (mostly effected by