Welcome to MilkyWay@home

Slow Compute Times for N-Body Simulation

Questions and Answers : Windows : Slow Compute Times for N-Body Simulation
Message board moderation

To post messages, you must log in.

AuthorMessage
Andrew

Send message
Joined: 8 Mar 20
Posts: 2
Credit: 1,113,451
RAC: 0
Message 71756 - Posted: 15 Feb 2022, 3:20:42 UTC
Last modified: 15 Feb 2022, 3:20:54 UTC

Not sure how wide spread this issue is, but I've noticed on the N-Body Simulation units running with 2 cores and a description ending with "(nt)" (I think that's what it was) that I'll get to about 0.37% before my remaining time estimate takes off. Before aborting, one task was estimated at over 700 days! My computer is a custom build and is a few years old, but up until very recently, it's been able to support all but these new work units without issue. I've had it running several other projects (WCG, Rosetta, LHC, MLC, etc) and they all seem to run fine. I think there may be a bug in these work units. When I see ridiculous estimates such as 700 days, it leaves me to believe a process got stuck in a loop. I've since adjusted my compute preferences the Separation 1.46 tasks since they've been able to run without issue.
ID: 71756 · Rating: 0 · rate: Rate + / Rate - Report as offensive     Reply Quote
Profile Keith Myers
Avatar

Send message
Joined: 24 Jan 11
Posts: 696
Credit: 540,079,140
RAC: 86,701
Message 71757 - Posted: 15 Feb 2022, 21:32:25 UTC - in response to Message 71756.  

The N-body tasks are (MT) multi-thread and normally would run with all your cpu threads available. So limiting them to only two cpu threads will slow them down a bit.

But more to the point . . . . until you have completed 11 valid N-body tasks, the estimated times to completion will be completely invalid.

Only after the 11 valid tasks will the APR for the app on that host has been calculated will the estimated times to completion will be accurate.

Since your computers are hidden, I can't tell if you have reached that point yet.
ID: 71757 · Rating: 0 · rate: Rate + / Rate - Report as offensive     Reply Quote
Andrew

Send message
Joined: 8 Mar 20
Posts: 2
Credit: 1,113,451
RAC: 0
Message 71759 - Posted: 16 Feb 2022, 5:34:57 UTC - in response to Message 71757.  

The computers should be visible now. As far as the limiting - I had forgot that I reduced the number of cores that BOINC was allowed to use, so that makes sense. I'll have to adjust those settings to allow the sims to run quicker.
ID: 71759 · Rating: 0 · rate: Rate + / Rate - Report as offensive     Reply Quote

Questions and Answers : Windows : Slow Compute Times for N-Body Simulation

©2024 Astroinformatics Group