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What Improvements Will 64-Bit Processors Bring?

Posted by Cliff on from the kibbles-n-bits-and-more-bits dept.

RyanG asks: "Everyone always looks at numbers (MHz, RAM, HD) when they're considering buying a new computer. Recently, more users have been eyeing bits, as in 64-bit processors, namely the Itanium and to a lesser extent the G5. A lot of people remember the performance increases that were seen when moving from 16 to 32-bit processors and some people seem to think similar performance increases will be realized when moving from 32 to 64-bit pocessors. From what I've read this isn't going to be the case given that 64-bit percision isn't needed in all but a few cases and that moving around that extra data can actually hurt the performance of 64-bit processors when compared to 32-bit processors. Anyone care to comment?"

2 of 69 comments (clear)

  1. Re:Average Joe Doesn't Push It by green+pizza · · Score: 4, Interesting

    Very well said. However, I did want to make one point.

    (you gamers who say you can tell the difference between 100 and 125 FPS are lying... that's 1.5 to 2 times your monitor's refresh rate)

    I typically can't stand gamers, but I do understand their desire for framerate. The typical PC game has no mechanism for holding a sustained framerate, nor are things like texture preloading handled with any sort of elegance. Most PC games use weak code and brute force to produce any acceptable output. As such, the machine with the highest average framerate is the machine that's the least likely to get into a situation where the framerate will drop below, say, 30 FPS... perhaps in a complex scene or hitting a spot of particularly bad code.

    That said, the nitpicking "this 3D accelerator is better because it's 10.2% faster" blurbs are mostly BS.

    Then there's the other end of the spectrum. The company I work for has an SGI-powered RealityCenter for engineering review and presentations. The 30-foot-wide screen is curved and lit by three Barco projectors. It's normally driven as either 3840x1024 super-wide using all three projectors, each driven by a graphics pipe. For more complex scenes, three pipes work in parallel to drive just one projector at 1280x1024. Most of our software is created in house with the help of SGI IRISPerformer and MultiGen-Paradigm Vega libraries. Aside from a few exceptions, the whole setup runs at a locked 60 Hz (60 FPS gfx and projector).

    For those that like tech specs, the machine behind the curtain is a Silicon Graphics Onyx2 installed in early 1999. It has 24 MIPS R10000 CPUs each with 8 MB of L2 cache and running at 250 MHz. 48 GB RAM and 1.8 TB of disk via four channels of gigabit fibrechannel. The graphics pipes are three InfiniteReality2 subsystems, each with four Raster Managers (64 MB of dedicated texture ram plus 320 MB of generic graphics ram per pipe). There's a DPLEX module on each pipe to allow all three to work in parallel when needed.

    If the bean counters approve, we should have a totally new Onyx3000 system installed by June 2002. After all, our current setup is about 3 years old... ancient by computer terms. Thankfully the projectors, lighting controls, and indeed most of the room (seating, conference table loft, etc) will be reused.

  2. Some advantages nobody's touched on yet.. by cmowire · · Score: 4, Interesting

    Some advantages nobody's touched on yet..

    1) Easier implementation of large filesystems. 2^64*512 bytes of disk space per filesystem should be good enough for quite a few increments of Moore's Law. Ditto for larger than 4 gig files.
    2) 64 bit processors take better to certain implementations of NUMA. SGI's implementation of NUMA gives each processor a range of memory that is local to that processor. If you had a 64 processor NUMA cluster, you'd have 64 megs local to each processor with 32 bit processors. You could have a few gigs per processor with 64-bit addressing.
    3) With 64-bit processors, it's easier to map a file to memory again, without needing to map individual chunks. Over the near term, you could map your entire disk drive to memory space.
    4) There are cases (i.e. bit packing) that don't take too well to vectorized MMX/SSE/etc. processing but do take well to 64 bit registers.
    5) The ability to segment your memory space without creating annoying limitations. As in, you can have the lower 8,388,608 terabytes of RAM reserved for the user and the upper 8,388,608 terabytes of RAM reserved for the kernel. As opposed to Windows 2k, which leaves 2 gigs for the user and 2 gigs for the kernel. With the possibility of 3 gigs for the user, if you are running a higher-end version.
    6) The ability to cache a data structure in the RAM attached to a given machine instead of buying solid state disk drives or other such things.

    --
    Gentoo Sucks