I have two machines running CPDN. One of them is a. slower and b. not on nearly as often. It has a task in the pipeline that has not been started yet. Can I pinch this task and put it onto the other faster machine if it is still not started when the faster machine runs out if there are no tasks available at that time?

Dave

Yes. But ...

The 2 OSs must be the same, (both Windows, or both Linux), (and possibly the BOINC version, because the structure of newer versions is changing), and there may be some problems with the server getting confused about why the data is coming from a different computer to which it sent that model. What the difficulties will be varies, and you'll just have to try it and see.
There'll also be difficulties if one machine is VERY much faster than the other. Something to do with estimated time to finish. This was posted about a couple of years ago, and I don't remember the details. (I think that the computer may 'run out of time' to complete the model.)
And some/all of these problems may only apply if the model has actually started on the slow machine.

The method to do all of this is just a backup and restore, but with the data zipped and saved onto, e.g., a cd, ram card, external hd. The zipping is to preserve the read/write attributes.
You should also save a copy of the client_state.xml from the fast machine BEFORE copying the data to it. Then you can edit the client_state.xml that came from the slow machine, so that the <rpc_seqno>, which is found in the <project> section, is the same is what was in the client_state.xml from the fast machine.

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Backups: Here

Dave, I'm afraid you can't do it. One of your computers is Windows and the other Linux. Each model is made for one OS only and has to be run on it from start to finish. The compilations are different for each OS. Sorry.

If both computers had been Linux or both Windows the idea would have been perfectly feasible.

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Thanks Les, I will try but only if the faster machine runs out of work and the slow machine has not started the task. - The slow machine is windows and the faster Linux so I realise that if started it won't work.

Dave

Dave

The executables for the 2 OSs are different, as are those for the Mac.
And the many data files that are bundled with each executable are matched to it.

I wrote my post in general terms for those in the future who want to swap between computers.
With a warning near the beginning about this not working across different OSs.

If you want the short answer for your particular case, IT WON'T WORK, as Mo has said.

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Backups: Here

It won't work whether the task you'd like to run on the other computer has started or not. Each model contains its OS-dependent compilation as an intrinsic part of itself; this intrinsic nature is defined for us even before download and cannot be changed by us crunchers. Each model type is made in three varieties: Win, Linux and Mac. When our Boinc requests a new model the CPDN server detects which of these three OSs we have and sends us the model with the compilation to match.

So I have to agree totally with Les. It isn't worth trying this.

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Thanks Mo and Les, It may be relevant for me in the future but I understand not with my current set up! At some point in the future I might get the second machine swapped to linux. That would be the easy bit. It is converting my other half that is not so easy! I hadn't realised the bit about the OS-dependent compilation and thought that as long as the model hadn't started I would stand a chance. I may also be getting a second nix machine later this year so if I do your answers may still prove useful to me.

Thanks again

Dave

In the meantime I ought to update the instructions I wrote quite a while ago about moving the Boinc Data folder from one Windows machine to another. The post about this is in a CPDN Readme but an update would probably be useful eg wrt the location of the folders.

It will still be relevant for Linux machines because the concepts are the same though some of the terminology will be different.

It's useful for anyone who plans to scrap or give away a computer but wants to complete the models.

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