Re: [RFC] TuxOnIce

[Pavel Machek <pavel@ucw.cz>]

Hi!

> I'd like to submit TuxOnIce for review, with a view to seeking to get it
> merged, perhaps in 2.6.31 or .32 (depending upon what needs work before
> it can be merged) and the willingness of those who matter.
> 
> To briefly summarise the advantages to merging TuxOnIce:
> 
> - Support for multiple swap devices
> - Support for non-swap (an ordinary file can be used)
> - Uses cryptoapi (LZO support, more than 2x speed of uncompressed data!)
> - Asynchronous I/O, readahead, multithreaded. Get the maximum throughput
>   possible with your hardware.
> - Userspace user interface that lets you abort hibernating and abort
>   resuming, get nice progress display etc.

All these are either done by uswsusp already, or could be done w/o
modifying kernel code.

> - 8 years of testing and improvement.

Yeah, 8 years of out of tree testing; while current code is used by
basically every distro out there.

> - Full image of memory (LRU pages that don't need to be atomically
>   copied are saved prior to the atomic copy, then used as the
>   destination of the atomic copy).

Yeah, that was the patch that did not go in

> - Support for resuming a different image after writing an image - makes
>   powering down a UPS after writing an image doable.


This can  be done w/o kernel code. Someone had a patch...

> - Simple to set up (works without any userspace binaries, uses existing
>   resume= and noresume commandline parameters).

Given that distros ship uswsusp already... is that really an advantage.

To summarise disadvantages:

- only core has 8000 LoC
- it does stuff that can be easily done in userspace
     (and that todays distros _do_ in userspace).
- it duplicates uswsusp functionality.
- compared to [u]swsusp, it received little testing

									Pavel

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