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Re:Compute Engine machine types with up to 96 vCPUs and 624G... by malux85 on Friday October 06, 2017 @07:35AM (#15415940)
scientific computing and simulation. I have had need for machines like this - for a project that was very compute heavy but embarrassingly parallel, but also was very "chatty" - I.e updated the data structures a lot during compute

I can't be too specific about it, but if involved creating a very large tree structure and updating, pruning and transversing the tree a lot

If the algorithm is updating and reading a large data structure a lot it's only practical from a speed point of view to hold the whole structure in RAM

Re:Compute Engine machine types with up to 96 vCPUs and 624G... by neutronicus on Friday October 06, 2017 @09:29AM (#15416602)
Is this really a better solution than just getting hours on NERSC (or some other government supercomputer)?
Re:Compute Engine machine types with up to 96 vCPUs and 624G... by tallanvor on Friday October 06, 2017 @12:03PM (#15417859)
Private companies want to do simulations as well, and with this type of solution, you can pretty much run them on demand rather than having to wait in line.
Re:Compute Engine machine types with up to 96 vCPUs and 624G... by neutronicus on Friday October 06, 2017 @01:23PM (#15418503)
...I guess.

My advisor's company straddles the public / private divide, but we've definitely done some simulations for private clients on NERSC, and I assume we weren't misusing hours allocated for some other purpose.

Re:Compute Engine machine types with up to 96 vCPUs and 624G... by mahdix on Friday October 06, 2017 @07:56AM (#15416046)
That's interesting. What tools do you use to run your computations in parallel on a cluster? Hadoop?
Re:Compute Engine machine types with up to 96 vCPUs and 624G... by malux85 on Friday October 06, 2017 @07:59AM (#15416060)
For this type of problem - it must be done on a single node. The overhead of network communication would have killed the latency requirement - that's why we need a huge machine like this.

The code was written in C

(We also maintain a Hadoop and Cassandra cluster, and I use Spark for distributed computation - but those are different projects)

Re:Compute Engine machine types with up to 96 vCPUs and 624G... by make3 on Friday October 06, 2017 @07:46AM (#15415994)
how does the problem fair on gpus
Re:Compute Engine machine types with up to 96 vCPUs and 624G... by hyperbovine on Friday October 06, 2017 @07:54AM (#15416031)
If it requires synchronizing across workers, poorly.
Re:Compute Engine machine types with up to 96 vCPUs and 624G... by make3 on Saturday October 07, 2017 @05:55PM (#15425903)
depends how often you need to synchronize. look at deep learning, you need to sync the weights as often as possible
Re:Compute Engine machine types with up to 96 vCPUs and 624G... by malux85 on Friday October 06, 2017 @07:55AM (#15416037)
This is correct