Questions tagged [io]
The process of Inputing and Outputting information, particularly emphasis on user generated input/output at runtime.
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Parallel output in ASCII-format with MPI
After some parallel computations, I need to write the results in a file and for plotting reasons, I want them in ASCII format. Because of performance issues, I want to avoid to ...
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Regarding Amdahl's balanced system law [closed]
One of the paper titled "Rules of Thumb in Data Engineering" (Jim Gray et. el.) mentions some calculations based on Amdahl's balanced system law.
Link to paper: https://www.microsoft.com/en-us/...
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Memory/speed tradeoff for many small matrix inverses
Problem
In the case of a finite element code, I have many small (order of 30x30) matrix inverses (or LU factorizations), one per finite element. These matrix inverses never change and must be applied ...
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A fast I/O file format readable by Fortran, Java, PHP?
I am writing a Fortran program that does fairly light weigt computation on fairly large data files. The output must be readable by some Java-script (that i have no insight in) and preferably also by ...
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Many processors reading a single HDF5 file
I'm working on a code that we eventually plan to scale up to 10's or 100's of thousands of processors (using MPI). I have a single HDF5 file (mesh nodes and connectivity, etc) that needs to be read ...
- 542
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What are the most common dense matrix storage formats?
I'm looking to write some code to read in a dense matrix from a file, and I was wondering what are the most common storage formats that my code should support?
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Converting matrices L and U output by dgssv() of SuperLU to triples format
How can I convert matrices L and U output by dgssvx() of SuperLU to triples format (to ...
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3
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How do I read a binary file into PETSc as a matrix?
I created a binary matrix using the following loop in c
...
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Outputting a distributed vector in PETSc
I'm working with someone else's code that uses PETSc 3.0.0-p9.
They have a vector at the end of the computation that is distributed among a number of different processors, and I want to output that ...
- 1,155
6
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2
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Performance of Lustre filesystems
The cluster I work on has a filesystem labelled as "fast" with no further explanation. But the filesystem type is "lustre", which strongly hints at a Lustre filesystem. While general information about ...
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How to deal with too much data?
Our plasma dynamics simulations often produce too much information. During the simulations we record various physical properties on a grid (x,y,z,t) that is as large as (8192x1024x1024x1500), for at ...
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Parallel I/O options, in particular parallel HDF5
I have an application that can be trivially parallelized but its performance is to a large extent I/O bound. The application reads a single input array stored in a file that is typically 2-5 GB in ...
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