- This topic has 5 replies, 4 voices, and was last updated Nov 15-5:38 am by fungalnet.
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olsztyn
First, pardon me if I am supposed to know it by now:
Before I encountered AntiX I had been playing a lot with persistence on live distributions of Mint, Peppermint an Lubuntu. Persistence file format there (I think for the entire Ubuntu family) is called Casper, if I am not mistaken… From my (humble) experience I had lots of reliability problems with such persistence (Casper based). E.g. for no explainable reason such Casper persistence file went corrupt. Not once but on many different USB sticks unpredictably. At that time (a few month ago) I gave up relying on persistence for Live OS.Now, I have been using a lot persistence on AntiX on many sticks and it appears so far 100% solid. Not a single case of corruption…
What can be accountable for such dramatic difference? Architecture? AntiX simplicity? Systemd Free (I do not think this would be the reason, I am just throwing in for the lack of other ideas…)?
Thanks and Regards///Live antiX Boot Options (Previously posted by Xecure):
https://antixlinuxfan.miraheze.org/wiki/Table_of_antiX_Boot_ParametersAnonymous
Prior to replying, I skimmed/read the latest casper v1.399 code https://launchpad.net/ubuntu/+archive/primary/+sourcefiles/casper/1.399/casper_1.399.tar.xz
The antiX persist-save operation explicitly calls sync
The kernel keeps data in memory to avoid doing (relatively slow) disk reads and writes. This improves performance, but if the computer crashes, data may be lost or the file system corrupted as a result. sync ensures that everything in memory is written to disk.
This explicit call seems to be absent from the casper-snapshot script. If that’s the case… Possibly, occasionally, when writing to a comparatively slow usb device, when the casper operation reports “ok done” and exits, shutdown/poweroff proceeds before the usb device has fully written the changes.
Another difference: by default (meaning, you can edit the the exclusion lists to customize) the antiX persistence and remastering utilities ignore/discard changes to web browser cachefiles and apt cache downloaded .deb packages. If the casper operation involves (needlessly) re-re-re-writing changes to these myriad files — and AFAICT it does — comparatively, that’s a lot of extra writing. In addition to inviting premature wearout of the flash storage device, casper’s larger/longer write operations would be more prone to failure due to interruption (e.g. incomplete writing, shutdown commences while to-be-written content still remains in the pendrive controller’s write buffer).
Thank you for this extensive info. Looks like these differences would account for problematic behavior of Casper and solid design of AntiX persistence…
Also it looks to me that due to the lack of integrated remastering (at least not integrated at hand as in AntiX) the length of life of Casper persistence just increases the likelihood of corruption. At some point it is likely to get into the issues you describe.Live antiX Boot Options (Previously posted by Xecure):
https://antixlinuxfan.miraheze.org/wiki/Table_of_antiX_Boot_Parameters
anticapitalista
Maybe I’m behind with the times with Casper, but IMO it was always a half-hearted attempt at running persistence, unlike the persistence used by Knoppix and Puppy (we were influenced more by them than Ubuntu/casper). We worked hard on our live features and I really believe we have the best live persist/remaster/frugal options in the linux world.
Philosophers have interpreted the world in many ways; the point is to change it.
antiX with runit - leaner and meaner.
We worked hard on our live features and I really believe we have the best live persist/remaster/frugal options in the linux world.
It certainly looks this way. Not only most flexible and well designed but also rock solid!
Thank you…Live antiX Boot Options (Previously posted by Xecure):
https://antixlinuxfan.miraheze.org/wiki/Table_of_antiX_Boot_Parameters
fungalnet
This article I recently read seems to may be of interest to people looking at this thread.
https://lwn.net/Articles/664688/ Persistent BPF objectsI recently tried a young linux project called adelie https://wiki.adelielinux.org which included this option and I had to go searching for what it is.
- This reply was modified 4 years, 5 months ago by fungalnet.
anti-X - Adélie - obarun - systemd Free Space
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