Hi

I have a machine running 4 HADCM3 models (they pre-date the optimized IO versions). Four models because I\'m using a dual processor hyperthreading box under Windows XP. All four models are at around 60-61%.

Now, it looks like I may be changing projects in a couple of months, and no longer have access to the machine doing the processing. Continuing the processong on that box is not an option in that case. I think the models will be at around 90% completed at this time, given the present speed.

Should I, when the time comes, i) continue the models on a Core 2 Duo WinXP based machine to which I have access, or ii) abandon them? Credit doesn\'t matter to me, but what\'s best for the science? The former option would make the Jan 8th 2008 deadline without problem.

If I were you, I would transfer them and complete them. The project is content with models that are incomplete (i.e. they will be used in data analysis), but it must be better for them to have a complete model.

I\'ve transferred models from one machine to another without any problem. Just make sure you archive any existing BOINC installation from the target machine (or delete it), copy the whole BOINC folder from the source machine. For good luck, you could then re-install BOINC on the target machine: BOINC seems to be very good at preserving the data when new versions are installed, and you\'ll then have all the icons set up as intended.

You will then get a new machine reported in your results pages, which you can merge if you want.

Best of luck.

Great, thanks for the info.

I\'ll keep crunching away at full speed for a couple of months, and move as you described if it proves necessary. I can\'t give up having got this far!

They will process a ton faster on the C2D, even though you are only doing 2 at a time.

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They will process a ton faster on the C2D, even though you are only doing 2 at a time.

As I\'d be copying my entire BOINC directory, I\'d be running my current 4 (not 2) models in parallel on the C2D. I guess I could suspend some of them. Also, the 2.33GHz C2D (Merom, not Conroe) seems to be similar in speed to the twin single-core 3.6GHz Netburst Xeon box I\'m using at present. Let\'s just not talk about power consumption :)

It\'s actually worse than that - the C2D box is already running two models under OS X. Were I to transfer the other 4 work units, they\'d have to be hosted under Parallels + Windows XP, which can only use one of the two processor cores. So I fully expect the \"from Xeon\" models to run at 1/4 their previous speed. It\'ll get the job done though. Good job the box has 2GB RAM!

If I suspend a work unit for 2-3 months, then continue it, does that cause any problems? What\'s the \"not heard from you\" delay before CPN assumes the WU is dead and gives it to someone else?

It\'ll be fun merging the dual Xeon box with a virtualized XP machine :)

If I suspend a work unit for 2-3 months, then continue it, does that cause any problems? What\'s the \"not heard from you\" delay before CPN assumes the WU is dead and gives it to someone else?

It\'s said to be six weeks. However, I\'ve not noticed that work units really are reissued on these timescales - anyway, a five week refresh should keep them!

It\'ll be fun merging the dual Xeon box with a virtualized XP machine :)

Oops. I should\'ve checked your computers before recommending a transfer... Good luck with the emulation.

Well, the virtualization runs pretty close to native speed (I\'d never dream of attempting this with true emulation like Virtual PC on a PowerPC chip), albeit on one core only. I\'ve just stopped BOINC, burnt the directory to a DVD and re-started it. Will give the copy a go on a WinXP VM tomorrow evening, naturally I won\'t give this VM network access for this test.

Doing a round-robin on the workunits seems a good way to process them efficiently while keeping them alive.

I\'ve just stopped BOINC, burnt the directory to a DVD and re-started it.

Just FYI in case you are not aware...if you copy/burn the BOINC directory directly to CD/DVD, and then copy it back to the same or another PC from the DVD, you will likely get read only attributes on the restored BOINC directory. This, of course, causes all sorts of problems after startup as BOINC tries to write to write-protected files. So, you may need to change attributes of the BOINC directory structure after restoration. Or zipping up the directory before archival to DVD and unzipping to restore works fine.

Thanks for the tip.

Well, under Parallels / WinXP, I installed BOINC, copied the 1.8GB of data for my 4 models (setting the files read-write), and disabled the network (to avoid duplicate trickles). Works perfectly. So if the time comes, I\'m all set :)