Sun cuts wires out of chip connections

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Well, part of that is what 64 bits are for.: Disk drives are currently used for two things: long-term non-volatile storage of persistant data, and temporary storage of virtual memory paging or other temporary files.

The only reason you have to have virtual memory is because 32-bit and smaller processors cannot address enough physical memory. You cannot have more than 4GB of total addressable memory (and that includes memory-mapped I/O, BIOS ROMs, and the like, as well as straight-up RAM) in a 32-bit system. This is nowhere near enough to, for instance, perform memory-hungry operations on a huge (e. g. full tabloid 2-page spread size at 300dpi 16-bit CMYK) image in Photoshop, let alone work with a movie in Premiere or Final Cut Pro, so in such programs you actually only work on a part of the image or movie in memory at a time, and the rest is swapped out to disk.

Going to 64 bits increases the total addressable memory space to 18,446,744,073,709,551,616 bytes (18 ExaBytes -- over eighteen QUINTILLION!). Of course, RAM chips anywhere NEAR that big are far into the future, but the point is that there is no hard limit that will be a practical limit any time soon.

Even now, it would be reasonably feasible to have a system with, say, 64GB of RAM. Such a system could edit a two-hour movie in SDTV resolution, or a half-hour TV show in HDTV resolution, at low compression ratios, and hold it all (including the OS, application(s), etc.) in RAM throughout the process. No swapping to hard drive. No need for RAID 0 arrays to stream the video for previewing because single hard drives are still too slow.

Combine this with Sun's older vision of using broadband Internet servers for all long-term storage, and you completely eliminate the need for a hard drive of any kind in the system. The only mechanical storage would be a DVD burner, and even that may become obsolete.

One thing I've wondered is why the makers of 64-bit Athlon64 or Opteron motherboards haven't made a mode which, if a 32-bit OS is booted, converts all RAM past the 3GB mark into a virtual ATAPI RAM drive that looks to the system like a super-fast hard drive. Say you have 8GB of RAM. When running a 64-bit OS, you get all 8GB as system RAM. But when running a 32-bit OS, you get 3GB of system RAM (the remaining 1GB of the 4GB space is for memory-mapped I/O and other system stuff), and the other 5GB appears as a hard drive. It's volatile, of course, and so would not survive a power-off, but that's just fine for your Virtual Memory swap / paging files, your TEMP directory, your Photoshop Virtual Memory, etc. etc. etc. And, since no physical heads are involved, you'd never have to defrag it, since RAM takes very little if any more time to read fragmented data than it does to read contiguous data (indeed, that's where the "RA" in "RAM" comes from: RANDOM-ACCESS Memory)!; Posted by: Joel R Posted on: 08/06/04 You are currently: a Guest | Members login | Terms of Use