Re: Hibernation Redesign

On Wednesday, 11 July 2007 14:29, Miklos Szeredi wrote:
Freezing of tasks is slowing down suspend. Don't know how serious
this is, suspend is pretty fast, but could possibly be even faster.

It's FUD. Freezing of tasks normally takes next to no time. I've never
understood the rediculously long timeout it has. If freezing succeeds, all
processes are frozen within 1/2 a second tops. If it fails, nothing is going
to change in the following 19.5 seconds (or whatever it is if I don't
remember the value properly).

Right. The 20s timeout is again a sign of brokenness.

Are you still serious?

If we expect something to fail, it should fail immediately, without
waiting for arbitrary timeouts.

I don't agree. If you think so, then please tell me what the softlockup
infrastructure is for.

And if we don't expect it to fail, why the timeout?

We know that it can fail, so we use the timeout to detect failures.

Of course we know it can fail (network problems, etc), so it's wrong
whatever way we look at it.

Are you trying to say that whatever can fail is wrong?

No. Sorry about the sloppy sentence.

What I was trying to say, is that if we _know_ that the suspend can
fail, it is wrong to have a timeout to determine that it will fail.

Hmm, I'm not sure what you mean ...

If there are conditions in which it's not a good idea to hibernate (let's
consider hibernation only for clarity), I think we can use a timeout.

Greetings,
Rafael


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"Premature optimization is the root of all evil." - Donald Knuth
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Relevant Pages

  • Re: Hibernation Redesign
    ... this is, suspend is pretty fast, but could possibly be even faster. ... Freezing of tasks normally takes next to no time. ... The 20s timeout is again a sign of brokenness. ... We know that it can fail, so we use the timeout to detect failures. ...
    (Linux-Kernel)
  • Re: Hibernation Redesign
    ... Freezing of tasks normally takes next to no time. ... The 20s timeout is again a sign of brokenness. ... If we expect something to fail, it should fail immediately, without ...
    (Linux-Kernel)
  • Re: Hibernation Redesign
    ... It's FUD. ... Freezing of tasks normally takes next to no time. ... The 20s timeout is again a sign of brokenness. ... We know that it can fail, so we use the timeout to detect failures. ...
    (Linux-Kernel)
  • Re: Hibernation Redesign
    ... It's FUD. ... Freezing of tasks normally takes next to no time. ... The 20s timeout is again a sign of brokenness. ... If we expect something to fail, it should fail immediately, without ...
    (Linux-Kernel)
  • Re: Hibernation Redesign
    ... this is, suspend is pretty fast, but could possibly be even faster. ... It's FUD. ... Freezing of tasks normally takes next to no time. ... The 20s timeout is again a sign of brokenness. ...
    (Linux-Kernel)