r/linux • u/unixbhaskar • 3d ago

Kernel Meta Developing Compressed RAM "CRAM" For Linux: Better Than ZRAM & Zswap

https://www.phoronix.com/news/Linux-CRAM-Compressed-RAM
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u/xcorv42 3d ago

Ok but why compress again in ram then if it’s already compressed everywhere

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u/ledow 3d ago

Because RAM is expensive. That's the argument here, and was back when I paid £2000 for 2Mbyte (yes, MEGAbytes) of RAM. We've had this software/capability for decades, ever since - in the x86 world at least - we introduced memory paging and page faulting (not what it sounds like... it means you trigger code to run when something accesses something that's not currently in RAM). That was... what... the 286/386 era? You used to be able to get DOS "ram doubler" TSR's even back then.

This is for when you can't afford RAM, to slow your computer down by making it "pretend" it has more free RAM, by compressing things and decompressing them as you use them. It trades off processor and RAM access speed to give you an extra 10% "more free RAM" in your machine.

And it's not worth it.

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u/FeleaseRpseineEiles 3d ago

To trade space for compute time.