Best practice for migrating work to a new machine?

[phillipsjk]

After the projected (run time) of my assigned primality tests doubled; I decided to move the assignments to my "white elephant" computer for completion.

Looking through the local.txt file I see:

OldCpuSpeed=XXXX
NewCpuSpeedCount=0
NewCpuSpeed=0
WorkerThreads=4
CoresPerTest=2
ComputerGUID=[redacted]35
ComputerID=[Redacted]
Memory=4000 during 7:30-23:30 else 4000
SrvrUID=[redacted]75
SrvrComputerName=[redacted]94
SrvrPO1=0
SrvrPO2=1
SrvrPO3=3
SrvrPO4=4000
SrvrPO5=4000
SrvrPO6=450
SrvrPO7=1410
SrvrPO8=1
SrvrPO9=4
SrvrP00=6
...

Based on how the CPU speed is updated, is it safe to assume I only need to set the GUID to '0' to get it to automatically update?

I am assuming the 'Srvr' entries refer to the specific machine I was sending results to, not my own machine.

[phillipsjk]

I found that the PRP backup files were larger than the available space on my USB stick (around 600MB). I solved that problem by being more selective in the files I copied over:

• Only the state of the 4 exponents I was working on (identified by date)
• 1 backup of each of the 4 exponents I was working on (another 120MB)
• local.txt and prime.txt
• results.* (probably not needed)
• worktodo.txt

[petrw1]

Originally Posted by phillipsjk

I found that the PRP backup files were larger than the available space on my USB stick (around 600MB). I solved that problem by being more selective in the files I copied over:

• Only the state of the 4 exponents I was working on (identified by date)
• 1 backup of each of the 4 exponents I was working on (another 120MB)
• local.txt and prime.txt
• results.* (probably not needed)
• worktodo.txt

Assuming you installed Prime95 on the new PC, I don't advise copying over local.txt or prime.txt … though you have need a few parms in them.
Only worktodo.txt and the first 2 files you listed.

[phillipsjk]

Originally Posted by petrw1

Assuming you installed Prime95 on the new PC, I don't advise copying over local.txt or prime.txt … though you have need a few parms in them.
Only worktodo.txt and the first 2 files you listed.

Prime.txt is explicitly supposed to be copiable from PC to PC (mentioned in the readme.txt).

Edit: I want to hand edit the local.txt because both machines are a NUMA. It is relatively easy to map L2 caches on the old machine to CPUs on the new one.

[phillipsjk]

Looks like I will be copying prime.txt and the running 4 instances: mprime is not NUMA aware. I have had problems in the past with cryptocurrency hashers erroring out when accessing "foreign" memory under load.

https://www.mersenneforum.org/showthread.php?t=22571

I guess the procedure would be approximately:

1. Extract mprime to 4 separate folders.
2. Copy one state file and backups (and prime.txt) into each folder.
3. copy worktodo.txt into each, then edit to match data files.
4. Run mprime configuration script; tell each instance (with an incremented name) to use 1/4 of available cores.
5. Review local.txt to make sure each instance is actually on a different CPU.