When The PCI Bus Departs

km790816 writes: "I was just reading an article in the EETimes about the possible war over the technology to replace the PCI bus. Intel has their 3GIO. (Can't find any info on Intel's site.) AMD has their HyperTransport. There has been some talk about HyperTransport going into the XBox. I hope they can agree on a bus. I don't want another bus standard war. So when can I get a fully optical bus on my PC?" Now that's what I'd like: cheap transceivers on every card and device, and short lengths of fiber connecting them up. Bye bye to SCSI, IDE, USB, Firewire ...

Comments

Look for PCI-X and InfiniBand

[Anonymous Coward]

Part of my PhD work is in this area and I just wanted to throw in some of the things I've seen..
First, in a nutshell, look for PCI-X. It makes PCI a switch based medium instead of a bus, will let you utilize your existing PCI devices.. Supposed to be very good for performance (Gigabytes/s) and will be out in a few months. This is the one to bank on..
The real competitor is InfiniBand. The big 7 are involved in this (includes Compaq, Intel, IBM, MS, HP..). Its huge, with an 800 page spec you can get online for $10. It may be used to replace local I/O infrastructure (ie pci), as well as comm between hosts (ie cluster computers). It functions as: an I/O replacement (pci), Storage area network solution (ie fiberchannel, smart disks), and System Area Networks (cluster computer interconnect..Myrinet, GEth, SCI). Multi-gigabit links, switched medium, memory protection for transfers between hosts, split dma transaction notions (ie remote DMA mechanisms)..InfiniBand is what happened to a lot of the smaller competing standards, btw..

A lot of people are not happy with IB. People see it as the big 7 trying to ram more hardware down our throats in a way that forces us to rewrite our OSes and do communication. Looking on the IB trade page and you will literally come across quotes along the lines of "InfiniBand(tm) is a knight in shining armor to save you from the monster of PCI".. Do we really need to have a new standard when 90% of the people out there use it for low-bandwidth soundcards, 5,000 gate ethernet transceivers....?

You MUST read this article about PCI-X vs IB:
http://www.inqst.com/articles/pcixvib/pcix.htm
grimace/Georgia Tech

Re:why not agp?

[Teferi]

Well, the basic answer is that AGP isn't a bus, it's a port. A bus can have multiple devices chained off a controller, but a port, only 1; each AGP slot on a motherboard needs its own controller chip. That's one reason you only rarely see mobos with multiple AGP slots.
There's also the basic reason that almost nothing besides gfx cards -need- the huge bandwidth and bus speed of AGP. :)

Anyone else notice that Timothy never knows...

[the_tsi]

...what he's talking about?

> Now that's what I'd like: cheap transceivers on
> every card and device, and short lengths of
> fiber connecting them up. Bye bye to SCSI, IDE,
> USB, Firewire.

Here the posting is about replacing the high-bandwidth (formerly local) bus in PC architechture, and he thinks the suggestion regarding an optical bus is to be used for the (relatively) slow I/O busses of IDE, SCSI, Firewire and USB?

I think there should be Metaeditors to handle the editors who talk before their brain starts working. Either that or Timothy should be disallowed from adding "his two cents" to a news posting.

-Chris
...More Powerful than Otto Preminger...

Re:Its not needed

[Brento]

PCI is 32 bit at 33MHz. This is 1000 Mbits per second. The only interface device that needs or ever will need more than that is Graphics cards, and they have AGP slots. Most of the devices we use can even be run over USB.

Is that like Bill Gates saying no one will ever need more than 640kb? Frankly, I use two graphics cards in my desktop, and the only reason I don't have three is that the cost of another LCD panel is ludicrous. As soon as they come down more, I want one more panel, and then I'll be happy. I hate having to settle for a differently-branded (and usually more expensive) PCI card just because I don't have more AGP ports available. Usually the cutting edge stuff only comes out on AGP.

Granted, I'm not playing Quake on all three at once, but the only reason I'm not is because I can't. I'd love to be able to play my driving games on all 3, with the left monitor being a left view, and the right being a right view. Or a view of my nearest competitor. Or even just a big rear view mirror. The possibilities are endless.

The next thing up is storage area networking. PCI cards can't handle the biggest SAN loads, like our DVD jukeboxes at work. We can only use one 300-DVD jukebox per server, because the bus load can't handle more. Think in terms of quad Xeon servers, and it'll make sense - you can indeed shuffle a lot of load across the bus and off the fiber network if you need it. (And no, it's not a single reader per jukebox, there's lots of readers in each jukebox.)

Interesting

[JediTrainer]

That is an interesting idea - that we might replace all of our device connections (the bus) with fiber.

To take that idea a bit further, would it be possible to implement a protocol which is extendable? For example, each device connected gets a dedicated strand of fiber. The system, when polling the device, can negotiate a frequency range and transmission speed dynamically.

If I understand things correctly, this can help the system decide where it needs to put its resources, because higher demand devices would want a higher frequency range and transmission speed (hard drives, video cards etc) where simple devices like the mouse and keyboard will only take a little bit.

I think it'd be a great way to build a scalable architecture which might be unlimited in capacity, and eliminating wasted bandwidth and resources.