Slashdot Mirror
IBM Promises More Memory In The Same Space
dcallaghan was among the many readers to write with news of IBM's announcement of new memory technology. The upshot seems to be on-the-fly compression in hardware, taking the tack of RamDoubler and other software compression utilities, but moving the actual data sqashing into dedicated (fast) chips. I hope this leaks out of "server only" land soon; I'd love to have 256MB for the price of 128 -- this would be especially nice with pricey notebook memory.
Compression CANNOT guarantee anything better than 1:1 ratio - it is ENTIRELY dependent on the data.
For data compression in memory to succeed, you MUST have an option to cache the "extra" memory to a swapfile incase the prediction logic fails and you run out of physical ram. If you do not, you will tank your system, bigtime.
Sorry, but I'm very leery of any "memory compression" - it requires OS support to function. Period. You aren't going to just plug in a miracle DIMM and make it work. I hope IBM is opening the spec (it looks like they are) and that OS development people quickly embrace this, or their hardware will take a nosedive in the market.
Is a caching system. From the article:
MXT is a hardware implementation that automatically stores frequently accessed data and instructions close to a computer's microprocessors so they can be accessed immediately -- significantly improving performance. Less frequently accessed data and instructions are compressed and stored in memory instead of on a disk -- increasing memory capacity by a factor of two or more.
Note two things: They are not compressing everything. They are not replacing the actual memory.
Most of the criticisms here are based on misunderstandings of those two things.
(Note that I'm guiltless. I posted a number of times before getting around to read it.)
The cake is a pie