Pelegant is taking too much time

[arahim]

I am running run2.ele on sequential and parallel version of elegant. On seq. elegant run is completed in ~ 5 minutes, while with pelegant program is still running even half an hour is passed. I am using pelegant with 12 processors. Will the syntax of the input file will be same in elegant and pelegant or some thing I have to change.

[michael_borland]

The problem is that you are asking for output of the particle coordinates every turn. Depending on your file system and the amount of computational work, this can have a major impact on overall performance. If you ask for every 10th turn, e.g.,

Code: Select all

w1: watch,filename="%s.w1",mode="coord",interval=10

or only the first 1000 particles, e.g.,

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w1: watch,filename="%s.w1",mode="coord",interval=1,start_pid=1,end_pid=1000

you'll get better performance.

You may also get some improvement from optimizing the write buffer size for MPI IO, e.g.,

Code: Select all

&global_settings
        mpi_io_write_buffer_size = 1000000
&end

--Michael

[arahim]

How should we select the optimum number of nodes and and optimium number of processors to track the single bunch in a storage ring to study the single bunch instabilities. I have taken number of particles 100000 in a bunch and tracking 500000 turns.