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A comment on The Linux kernel's inability to gracefully handle low memory pressure. Parent comment

Re:The Linux kernel's inability to gracefully handle low mem... by nathell on Tuesday August 06, 2019 @01:59AM (#20622561)
As crazy as it sounds, can that fast device be a ramdisk?
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Re:The Linux kernel's inability to gracefully handle low mem... by LargoLasskhyfv on Tuesday August 06, 2019 @03:56AM (#20623152)
Not crazy at all, very useful.

https://en.wikipedia.org/wiki/Zram

https://wiki.gentoo.org/wiki/Zram

https://wiki.debian.org/ZRam

Or Armbian, a Debian derivative for many RaspberryPi-like ARM boards, where it helps avoiding trashing the usual sd-cards, and holds the logs, with different compression algorithms for /var/log, /tmp and swap.

Their script is here:

https://github.com/armbian/build/blob/master/packages/bsp/co...

I really like how this enables a tiny NanoPi Neo2 with one GB Ram booting from a 64GB SD-Card in an aluminum case with SATA-adapter and a 2,5" HDD mostly idling to draw only about 1W from the wall socket, while clocking up from about 400Mhz to 1,3Ghz if it needs to. It's not the fastest, but sufficient.

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Re:The Linux kernel's inability to gracefully handle low mem... by GuB-42 on Tuesday August 06, 2019 @03:25AM (#20622968)
Exactly what I thought. Losing <5% of your RAM as swap space probably won't do much difference.

But if it solves problems, why doesn't the kernel automatically assign part of RAM as a virtual swap device, if the user allows it. It can help monitoring tools, and because the kernel knows it is not a real swap device, it can optimize its use.

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Re:The Linux kernel's inability to gracefully handle low mem... by pantalaimon on Tuesday August 06, 2019 @04:15AM (#20623247)
It's not that crazy, there is zram: https://www.kernel.org/doc/Documentation/blockdev/zram.txt
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