Hi! tell me whether there is a cache compression in liquorix? zcache was a great project:
https://code.google.com/archive/p/compcache/wikis/zcacheiozone.wiki
https://lwn.net/articles/562254/

and

https://oss.oracle.com/projects/tmem/dist/documentation/presentations/LSFMM12-zcache-final.pdf

this project still exist?
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I think that all this functionality got integrated into cleancache and frontswap:

www.kernel.org/doc/Documentation/vm/frontswap.txt
www.kernel.org/doc/Documentation/vm/cleancache.txt

These are both enabled in Liquorix, but I think it's a user settable setting to enable compression through a kernel parameter.
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Thanks!
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What kernel parameters use in clearcache? I can not find any information about it.
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I found:

https://oss.oracle.com/projects/tmem/dist/files/RAMster/ramster-howto.txt
https://www.kernel.org/doc/Documentation/kernel-parameters.txt
www.gossamer-threads.com/lists/gentoo/user/262895

And add kernel params:

tmem.cleancache=1 cleancache zcache

it has no effect !
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Yep, just checked the kernel source, parameters, and configuration, and zcache was removed at some point (if it was ever added). I would recommend making sure you have a swap file or partition since zswap is enabled in Liquorix, otherwise you can play around with zram: www.kernel.org/doc/Documentation/blockdev/zram.txt

I checked the LKML as well and there's no mention of any zcache development in the last 2 years. It seems that effort has been abandoned unless a developer is working on it independently from upstream.
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It looks like in 2013, zcache was removed to have proper testing in the -mm kernel tree: git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=96256460487387d28b8398033928e06eb9e428f7

Either way, for the purpose of what Liquorix stands for, having zcache enabled by default would go against the purpose of this kernel. Performing compression on in-memory cache would add CPU overhead to memory intensive tasks and on systems that have lots and fast ram, would reduce performance.

You can research and provide patches if you're interested, but if this feature is merged, it will not be enabled by default.
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