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Windows Memory Manager To Introduce Compression
jones_supa writes: Even though the RTM version of Windows 10 is already out of the door, Microsoft will keep releasing beta builds of the operating system to Windows Insiders. The first one will be build 10525, which introduces some color personalization options, but also interesting improvements to memory management. A new concept is called a compression store, which is an in-memory collection of compressed pages. When memory pressure gets high enough, stale pages will be compressed instead of swapping them out. The compression store will live in the System process's working set. As usual, Microsoft will be receiving comments on the new features via the Feedback app.
Welcome to 2014
"You're right," Fisheye says. "I should have set it on 'whip' or 'chop.'"
Except swapping to disk
Welcome to 2013! as it was then compressed memory was introduced in Mac OS X.
- Henrik
- when the Shadows descend -
Gee, an Apple product did this in the 90's, compressing memory segments assigned to processes not currently executing.
(see, for example, https://www.usenix.org/legacy/...)
The same product was Apple's first to use pre-emptive multitasking,
The product? Newton.
, which introduces some color personalization options, ...
You no longer have to put up with the blue screen of death. Now you have the option to have speckled, sparkled, opalescent, translucent, scintillating, coruscant, flourescent, effervescent blue screens of death.
sed -e 's/Chuck Norris/Rajnikant/g' joke > fact
This seems eerily similar to what SoftRAM was trying to do in the mid-90s. Anyone remember this? "Double Your Memory!" was it's claim and in fact the tagline on the box cover. This was back when RAM cost a fortune and everyone needed more than they had in order to run Windows 95. The company made a killing... at first.
https://en.wikipedia.org/wiki/SoftRAM
I actually worked for them, and I saw the whole thing happen from start to finish. It was quite a wild ride. Mark Russinovich and Andrew Schulman took a particular offense to the software and set about publicly dissecting it and working feverishly to prove that it didn't work. They thought the whole thing was a scam. I personally witnessed tests that indicated it was doing exactly what it said it did - however it was difficult to prove any worthwhile effect under realistic working conditions. It seemed that the primary problem was that the program needed to reserve a chunk of memory to do it's thing, then it had to make intelligent decisions about what to put in there. If it was wrong (i.e., it compressed something that the user was going to close anyway, and the user opened a new program instead of retrieving the compressed one), the memory was wasted and overall performance (of opening the new application) was diminished. The reduction in overall memory at the outset may have been putting a strain on the system which the codec was unable to outperform. To aggravate things, the software also performed a few well-documented registry tricks to optimize the pagefile settings which led critics to claim that is indeed all that it was doing.
The proof I saw, for example, if you made a spreadsheet with millions of 1s in each cell, then made a cell calculating the total of all the cells, with SoftRAM, the calculation would take a quarter of a second. Without SoftRAM, a ton of the data got swapped to disk and the calculation took like 30 seconds. However, as soon as you put realistic data into the spreadsheet, the improvement basically disappeared because it wasn't compressible enough with the algorithms they were using. They actually hired a very famous compression expert at the time, who liked to talk a lot and bill them at something like $350/hour or something crazy and it didn't seem to help at all.
Eventually the company lost a class action suit and had to refund millions back to customers. They were never able to recover, despite using their wealth to acquire and improve various products. A few of the products they put out were good, like the Mac RAM management tool (though it pre-existed, and really, the company ruined the design and marketing for it), others (like BigDisk which faked your system into believing multiple disks were one volume) had problems and could be extremely dangerous if used incorrectly.
Ahh, good times.
Does this mean I have to put HIMEM.SYS and EMM386.EXE back into my config.sys file? I think I still remember some of the MS-DOS edit commands.
You are welcome on my lawn.
I have a Mac and have therefore had compressed swap for some time now. Theoretically, it's much faster than swap, even if you have an SSD. But there's a tradeoff. When swapping, the disk is busy, but the CPU is free to do other work, although things bog down a lot when thrashing happens. When doing compressed swap, the memory management hogs the CPU, which means it's not free to run other programs, and the system slows down. And thrashing still happens. It's just that your laptop heats up more when it's happening, and things don't get any less sluggish.
Of course, the biggest problem is Safari. I'll get Safari Web Content processes taking up 10GB or more. There's obviously some kind of run-away memory leak going on. Always when my system bogs down, it's Safari that's taking up too much RAM. Quit Safari, and the system becomes responsive again.