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Reminder: Enable ZRAM on your Linux system to optimize RAM usage
- iberator 6mo agoI remember that back in around 2007 i was able to somehow mount a graphical card (ati similar to geforce2?) memory directly in Linux, and put my swap file there :); Great times. Slackware 8.1 i think. as for zram: somehow i dislike it. Nowdays ram is plenty and if not: better to have fast OOM than chug of death with swap. I also remember running NetBSD 1.3.1 and Slackware 3 on 386SZ 26MHZ with 2 mb of ram (nowadays hard limit is 4mb to boot due the large memory pages on x86 afik)
- Neywiny 6mo agoMuch agreed. Early OOM is so much better for me than swap. I have 128G on my work laptop, 96 on my personal desktop. If it doesn't fit in that, it probably means I'd need a terabyte or infinite amount of swap and that's just nonsense.
- sidewndr46 6mo agoThis reminds me of a question I answered on StackOverflow a long time ago. I pointed out the original question was asking the computer to allocate no less than 128 gigabytes of RAM. The poster refused to accept the answer because I "didn't solve the problem, only explained why the code did not work"
- Neywiny 6mo agoI mean I would indeed consider that a comment on the question rather than an answer. Unless the question was "why doesn't the work with less than 128GB of RAM?"
- Kim_Bruning 6mo agoThere's also kernel zswap, right? https://www.kernel.org/doc/html/latest/admin-guide/mm/zswap.html https://www.kernel.org/doc/html/latest/admin-guide/mm/zswap.... Oh right, definitely. Chrisdown wrote an article comparing the two: https://chrisdown.name/2026/03/24/zswap-vs-zram-when-to-use-what.html https://chrisdown.name/2026/03/24/zswap-vs-zram-when-to-use-... Zswap is supposed to degrade more gracefully. There's even some HN comments on it: https://news.ycombinator.com/item?id=47500746 https://news.ycombinator.com/item?id=47500746
- dlcarrier 6mo agoThe architecture of zswap does make more sense, because you might as well combine the low speed and latency of compression with the same from writing to storage.
- yjftsjthsd-h 6mo agoMy impression is that zswap will be the universally preferred option for compressed swap, but right now it doesn't work without disk swap behind it?
- esperent 6mo agoI've heard ZRAM mentioned before and I've just spent 5 minutes reading articles on it... Which is about the maximum I have time for these days when it comes to esoteric linux internals. What's the downside? Does it use much CPU? If I have enough RAM already, should I still enable it? One article says it can be mapped to /tmp to reduce i/o. Is that a good idea? This article is light on all of these kind of details.
- BenjiWiebe 6mo ago'Swapping' to ZRAM is far less painful than actual disk-backed swap. Sometimes I start wondering why the computer is a bit sluggish, and find that I've got several GB in ZRAM.
- ChocolateGod 6mo agoYou only want to use zram if you've got no swap device (e.g. a raspberry pi). If you do, you'll want zswap instead.
- rcxdude 6mo agoWhat's old is new again: I remember various hacks like this being popular in early android ROMs because the first android phones really didn't have enough RAM to support the OS well.
- phh 6mo agoWell, you stopped hearing about it, not because it stopped being used, but because its support became mainstream for a very long time. Google strongly recommends using zram on all devices, even on devices with a lot of RAM since like Android 10?
- cromka 6mo agoAsahi devs initially enabled ZRAM by default and then disabled it, now recommending against it, quoting instabilities and random weirdness.