Which is the real software suspend? [LWN.net]

Which is the real software suspend?

Posted Mar 18, 2004 5:15 UTC (Thu) by NCunningham (guest, #6457)
Parent article: Which is the real software suspend?

Pavel and I have since talked over IRC, and we're going to aim to merge Suspend2 into the kernel through a series of patches against Pavel's implementation, after which I will take over maintaining suspend to disk. This will take some time. My first draft of a plan looks like this:

1. Convert data to struct page pointers.
2. Extents infrastructure.
3. Convert data to extents.
4. Plugin infrastructure.
5. Split swap writing code and make a plugin.
6. Compression plugin.
7. Dynamic page flags infrastructure.
8. Memory pool infrastructure.
9. Split out image preparation.
10. Two pagesets support.
11. Proc interface infrastructure.
12. Swap file support.
13. HighMem support.
14. SMP support.
15. Nice user interface.
16. Freezer enhancements?

As you can see, it will take a while to merge the code, but this should be the end to the three versions problem. I'd also like to acknowledge the support of laclinux.com, who are in the process of donating an HT motherboard, CPU and memory so that I can actively maintain SMP and Highmem support.

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Nice!

Posted Mar 18, 2004 18:36 UTC (Thu) by Ross (subscriber, #4065) [Link]

I've been wondering about setting this up on my laptop. One caveat is
that I would like to have an encrypted swap partition when I move to 2.6.
Will the compression plugin support be through the cypto API? Will this
allow encrypted suspend images?

Nice!

Posted Mar 19, 2004 0:59 UTC (Fri) by NCunningham (guest, #6457) [Link]

There isn't a CRYPTO api plugin for suspend2 at the moment, but you could make one :>.

Suspend2 plugins work in a pipeline, so a crypto plugin could take compressed data, encrypt it and feed to the next plugin in the chain. It shouldn't be hard to implement, and people on the suspend list would certainly be willing to help.

Is SMP support for swsuspend in the cards?

Posted Mar 18, 2004 22:40 UTC (Thu) by Duncan (guest, #6647) [Link]

I haven't tried swsuspend2, but the current in-kernel implementations
don't do SMP. I have a dual Opteron system as my desktop that it'd be
very nice to be able to suspend while I'm not using it.

Duncan

Is SMP support for swsuspend in the cards?

Posted Mar 19, 2004 1:00 UTC (Fri) by NCunningham (guest, #6457) [Link]

Suspend2 currently only supports SMP under 2.4 kernels. That should change shortly.