Does H5Sselect_hyperslab need communication between processes in parellel HDF5 write? Because I found that one process call H5Sselect_hyperslab will cost little time, but 4 CPU call H5Sselect_hyperslab function will cost much more time.(Extremly slow in the situation that called hundreds of times). I don't know why ? Can any one give some explanation about it?
Several days ago, I asked the questions about the topic "Write and Read a large number of hyperslabs speed ?" , and didn't receive any reply , So I asked the above questions about function H5Sselect_hyperslab.
Does H5Sselect_hyperslab need communication between processes in parellel HDF5 write? Because I found that one process call H5Sselect_hyperslab will cost little time, but 4 CPU call H5Sselect_hyperslab function will cost much more time.(Extremly slow in the situation that called hundreds of times). I don't know why ? Can any one give some explanation about it?
No, the H5Sselect_hyperslab() routine does not communicate between processes in parallel programs.
Quincey
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On Sep 29, 2009, at 7:16 AM, tony wrote:
Several days ago, I asked the questions about the topic "Write and Read a large number of hyperslabs speed ?" , and didn't receive any reply , So I asked the above questions about function H5Sselect_hyperslab.
HDF5 1.8 includes a number of new features that offer many users of
HDF5 substantial performance improvements and expanded capabilities.
Many of these features can only be accessed via revised API calls.
To support these new APIs and new features in the HDF-Java products,
we need make changes to the current the HDF-Java products. The changes
may affect applications that use the HDF-Java products, especially
the HDF5 Java wrapper.
This document discusses what work is needed to support HDF5 1.8 in the
HDF-Java products and how the work is done. This document includes the
following sections:
=> Changes and updates to the HDF5 JNI.
=> Stages of supporting HF5 1.8 in all the HDF-Java products.
The main work discussed in the RFC is the changes and updates to JHI5 for
supporting the new APIs added HDF5 1.8 library. Changes will also be
made to the package names and class structure. Although the changes of
the package names and structure are not related to supporting HDF5 1.8
features, they will affect applications that use the HDF-Java products.
We are looking for your input.
