Does Liquorix incorporate KSM (kernel same-page merging), please? If not, do you have any plans to include it? I have been using the separate UKSM patch for some time, and it brings a definite improvement in overall memory usage. Many thanks.
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Hi Brian49,

Liquorix doesn't have KSM enabled by default. For the type of workload that Liquorix was optimized for, KSM's overhead does not offset the memory saved. That's better left to distribution kernels and servers that are used to run arrays of VMs where duplication is more common.

However, if you do find an article that shows memory being saved in common applications, I'd definitely re-enable it. Applications like Chrome / Chromium come to mind where each tab is its own process and memory space.

And as a side note, I've experimented with UKSM and found it highly unstable. I'm willing to give it a second shot if it's improved significantly since the last time I tried it a year ago.
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Thanks for responding.

I'm afraid I can't produce any documentation. However, if I compile a kernel, applying your patch followed by the UKSM patch, my system flies like a bird and with a reliable reduction in total memory usage.

This only happens with UKSM. Simply enabling "legacy" KSM within the kernel produces no benefit that I can detect. I don'r run any servers or VMs.
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In case You want UKSM You might want to take a look at: pf.natalenko.name/ ...
Also, I find it easy to enable KSMand I have same experience about „legacy“ KSM as You do...
Of course I might be wrong...
Update: This, of course, works in kernel which have:as mainline does... 4.3 here now. (it seems I was not reading carefully enough... ;) Mea culpa.)
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Thanks for commenting. I'm aware of the pf-kernel, and it works well on my desktop PC. My only reservation about it is that the developer doesn't feel able to support LTS kernel versions. For instance, he has left the 4.1 kernel hanging at 4.1.6 and moved on to 4.2, whereas mainline 4.1 is now at 4.1.9 and likely to receive many more updates over the next two years. The Liquorix 4.1 kernel is still being regularly updated.
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Damentz now and then updates the 'past' branch, in this case, 4.1, but he rarely if never maintains anything past the previous release, so your belief that liquorix will maintain 4.1 is not valid.

it's a pure coincidence that damentz even did the last 4.1 updates, he just did one yesterday, but often on the past kernel branch he just lets them sit, you can't at all count on the past branch being updated with the stable releases, nor can you count on the past branch even being the linux kernel ltr branch at all, I've followed this for years, and I can assure you, that doesn't happen, at least not in a way you can count on, and if it does, it's just coincidence.

And remember, 'past' becomes 4.2 when 4.3 is new stable current, so 4.1 will no longer be supported, at least that's how damentz has always done it in the past.

Nor can you count on new liquorix kernels using a gcc that is available on a ltr distro like debian stable or ubuntu long term support release, they are based around current gcc in debian sid/testing and ubuntu current release, not the long term releases of debian/ubuntu.

To be clear: liquorix 4.2 and 4.3 will be compiled with the gcc that is current in current ubuntu and debian testing/sid, so when 4.2 becomes the past branch of liquorix, it will be using the current, present, gcc version in ubuntu current/debian testing sid, and it will replace 4.1 in the past branch. At least that's how it's always been.

Further, updates to the past branch usually only happen for specific reasons, not because there is a new stable release for that major kernel version, it varies, you can't count on that at all though in the way you seem to think you can.
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Thanks for the clarification. I am coming round to the view that in future I will apply patches such as BFQ and UKSM manually to the latest vanilla kernel sources, as long as those patches are themselves kept up to date and compatible. At the moment the BFQ patch is being kept up to date; the UKSM one isn't, but so far it still works.
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Speaking of gcc: when could we expect gcc5 getting into picture?

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Liquorix will switch to GCC 5 when the next stable version of Ubuntu is built using GCC 5. That will probably be 15.10, but I'll have to verify once it's released.

On the other hand, this shouldn't be an issue in the future since Debian decided to stop specifically versioning GCC they did with the 4.x series and just include a single gcc-5 package. Going forward after the first gcc-5 built kernel, gcc compatibility issues should be a thing of the past.
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Thank You for 4.3 with gcc5... ;) Just got from a trip abroad and nice surprise... ;)
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