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Where are the Large RAM Systems?
CaptCanuk asks: "I've been charged with finding a system with 16 GB of memory and have had a really hard time in acquiring one (especially with a PCIE 16x slot). Linux is at the forefront of these 'large system memory' systems and beyond beta versions of Windows XP, is the only OS that supports the 64 bit memory addressing required to use this much RAM. When I asked large beige box wholesalers, I'd get comments from 'Why do you want a 16GB harddrive...you want MEMORY? are you sure?' to 'No motherboard supports more than 4GB of memory; everyone knows that'. Where are these mythical large memory systems? Do you think such workstation configurations will become pervasive in the future? Will it take Microsoft's Windows XP 64 bit to legitimize their existence in larger quantities?"
Because if you're a company looking for reliability and ongoing maintenance, a self-build isn't necessarily the first thing you think of. You're a beancounter looking for an ongoing support contract from a reputable OEM you've heard of before, possibly with onsite or couriered-in replacement clause.
I'd like to throw out the possibility of clustering instead, though (mostly cause it's on my mind because I've been dealing with several support cases on clusters recently). Why is this not an option for extra power, resilience, etc..
Screw you all! I'm off to the pub
...there all over the place:
Dell Itanium
HP Itanium
IBM Itanium
IBM eserver xSeries 445 8870 (88701RX) can take 64 GB of ram, that enough for ya? I got a wild idea, why don't the "editors" of Slashdot do a 5 second google search before posting pointless Ask Slashdot questions like this and save us all a lot of time. Hell, it might even improve the quality of the site!
How we know is more important than what we know.
Or, I went to AMD's page here and clicked on one of the manufacturers listed. Where I found this dual opteron supporting 16GB ram. Took me all of 2 minutes.
-- Hulver's site
http://www.appro.com/ do same damn fine boxes, including 1U (yes, 1U) quad (yes, yes, quad) operton boxes that take 32GB of RAM.
:(
I only wish the company I work for could afford boxes like that
Oh, and there's that "need" thing I keep hearing about.
CaptCanuk's Boss asks: I've been charged with finding a qualified employee to handle big computer purchases. Now that most tech jobs are shipped to India, qualified personell in USA and Canada should be easy to find, but my employees aren't even capable of browsing Dell's web pages. I've tried everyone at my company, but they just scratch themselves and make loud screeching noises, then get back to reading Slashdot. So I ask: Where are those mythical competent workers? On the moon? Because they sure as hell aren't posting to "Ask Slashdot".
The Apple XServe supports 16Gb of RAM, the just don't like to admit it. I found this image on their site while looking for stuff last year.
Whether to use a cluster or not depends heavily on the problem domain. Until very recently, clusters didn't work so well with large databases, etc.
You also seem to be shopping specs rather than throughput. Your mention of 16x PCIexpress is what gives this away. The only cards that support this now are high, high end graphics cards, and these cards don't even need it. There's no real difference between the AGP 8x and PCIex versions of these cards.
That said, you're not going to find what you're looking for in the beige box world. You're looking (realistically) at about 4 different venders: Windows: Dell, IBM, and HP. UNIX: IBM, HP, and Sun.
You're also only looking at servers (not desktop or towers).
My experience is with Sun, and a little Dell and IBM. So I'm going to speak to those. Sun makes magnificient hardware. Their support organization has had problems recently, but the hardware is good enough that we don't need it often. Sun's V880 servers are amazing. up to 8 CPU's and up to 32 gigs of ram, with great growth potential (12 PCI slots, several of them 64 bit, 66 MHz).
We've had lots of problems with our Dell hradware. Whole lines of their servers have been crap, and dell replaced thier 16xx line with their 17xx line for us for free. Our exchange server runs on a 6550 IIRC, which has at least 8 gigs of ram. This model probably can go higher in ram, but I'm not sure.
We've been really impressed with the IBM hardware we've started to purchase. It's been pretty stable, fun to work with, etc. IBM has a long history of making great servers. They probably have several models that will help.
Zapman
OS X does not totally take advantage of more than 4GB of RAM. It can address tons of RAM, but each running application is limited to a maximum of 4GB of addressable space in Panther.
When Tiger comes out, non-gui applications will be able to address the full 64 bit address space, however, GUI apps will remain limited to the 32 bit address space. See here for more info.
Doh!
Buy an SMP opteron box, they'll support all the memory you want and then some. Most of the Opteron motherboards I've seen in use have 4 memory slots per cpu socket. So for instance with a quad opteron boards you could stick 16x 4G sticks in it for 64G of ram. Incidentally, it's not that only linux supports "64-bit addressing". The memory addressability is a function of the processor and/or memory controller (which is integrated in the processor in the case of the Opteron). There is no processor I know that can actually physically address 64 bits of memory (which would require something on the order of 65,536x 256Terabyte sticks to fill). IIRC correctly, the Opteron memory controller can physically address 40 bits of physical memory, which puts the theoretical limit for it at 1TB of RAM.
11*43+456^2
One additional thing to consider if you are planning to use Windows is the 4GB process limit (which is NOT the same as a total memory limit) in a 'normal' Windows server.
/3GB switch, bla bla bla, ....).
i d= 69
The operating system (Windows Server Enterprise Edition) will work with more than 4GB memory, but a process running on that server can only address 4GB of memory, of which 2GB is reserved kernel space (in normal circumstances, not including the
Check out:
http://www.brianmadden.com/content/content.asp?
Of course there are some tricks and things you can do, but still... keep this in mind.
This is due to the fact that you are working on 32-bit hardware that can only address 4GB directly, as far as I understand. Does Linux have this limit too? Or are there other 'tricks' that the Linux kernel applies to go above 4gb? Maybe other Slashdotters can elaborate on this.