Technical Insights

Quincey Koziol, The HDF Group

“A supercomputer is a device for turning compute-bound problems into I/O-bound problems.” – Ken Batcher, Prof. Emeritus, Kent State University.

HDF5 began out of a collaboration between the National Center for Supercomputing Applications (NCSA) and the US Department of Energy’s Advanced Simulation and Computing Program (ASC), so high-performance computing (HPC) I/O has been in our focus from the very beginning.  As we are starting our 20th year of development on HDF5, HPC I/O continues to be a critical driver of new features.

Los Alamos National Laboratory is home to two of the world’s most powerful supercomputers, each capable of performing more than 1,000 trillion operations per second. Here, ASC is examining the effects of a one-megaton nuclear energy source detonated on the surface of an asteroid. Image from ASC at http://www.lanl.gov/asci/

The HDF5 development team has focused on three things when serving the HPC community: performance, freedom of choice and ease of use.

David Dotson, doctoral student, Center for Biological Physics, Arizona State University; HDF Guest Blogger

Recently I had the pleasure of meeting Anthony Scopatz for the first time at SciPy 2015, and we talked shop. I was interested in his opinions on MDSynthesis, a Python package our lab has designed to help manage the complexity of raw and derived data sets from molecular dynamics simulations, about which I was

Mohamad Chaarawi, The HDF Group

Second in a series: Parallel HDF5

NERSC’s Cray Sonexion system provides data storage for its Mendel scientific computing cluster.

In my previous blog post, I discussed the need for parallel I/O and a few paradigms for doing parallel I/O from applications. HDF5 is an I/O middleware library that supports (or will support in the near future) most of the I/O paradigms we talked about.

In this blog post I will discuss how to use HDF5 to implement some of the parallel I/O methods and some of the ongoing research to support new I/O paradigms. I will not discuss pros and cons of each method since we discussed those in the previous blog post.

But before getting on with how HDF5 supports parallel I/O, let’s address a question that comes up often, which is,

“Why do I need Parallel HDF5 when the MPI standard already provides an interface for doing I/O?”

Mohamad Chaarawi, The HDF Group

Second in a series: Parallel HDF5

NERSC’s Cray Sonexion system provides data storage for its Mendel scientific computing cluster.

In my previous blog post, I discussed the need for parallel I/O and a few paradigms for doing parallel I/O from applications. HDF5 is an I/O middleware library that supports (or will support in the near future) most of the I/O paradigms we talked about.

In this blog post I will discuss how to use HDF5 to implement some of the parallel I/O methods and some of the ongoing research to support new I/O paradigms. I will not discuss pros and cons of each method since we discussed those in the previous blog post.

But before getting on with how HDF5 supports parallel I/O, let’s address a question that comes up often, which is,

“Why do I need Parallel HDF5 when the MPI standard already provides an interface for doing I/O?”

John Readey, The HDF Group

Editor’s Note: Since this post was written in 2015, The HDF Group has developed HDF Cloud, a new product that addresses the challenges of adapting large scale array-based computing to the cloud and object storage while intelligently handling the full data management life cycle. If this is something that interests you, we’d love to hear from you.

 

Interestingly enough, in addition to being known as the place to go for BBQ and live music, Austin, Texas is a major hub of Python development.  Each year, Austin is host to the annual confab of Python developers known as the SciPy Conference.  Enthought, a local Python-based company, was the major sponsor of the conference and did a great job of organizing the event.  By the way, Enthought is active in Python-based training, and I thought the tutorial sessions I attended were very well done.  If you would like to get some expert training on various aspects of Python, check out their offerings.

As a first-time conference attendee, I found attending the talks and tutorials very informative and entertaining.  The conference’s focus is the set of packages that form the core of the SciPy ecosystem (SciPy, iPython, NumPy, Pandas, Matplotlib, and SymPy) and the ever-increasing number of specialized packages around this core.     

HDF Group is hosting a one-day workshop at the upcoming Federation for Earth Science Information Partners (ESIP) Summer Meeting in Asilomar, CA on July 14th. Please join us to learn about new HDF tools, projects and perspectives. There will also be an HDF Town Hall meeting on Wednesday afternoon July 15th...

John Readey, The HDF Group   We’ve recently announced a new viewer application for HDF5 files: HDF Compass. In this blog post we’ll explore the motivations for providing this tool, review its features, and speculate a bit about future direction for Compass. HDF Compass is a desktop viewer application for HDF5 and other file formats. A free and open source software product, it runs on Mac OS X, Windows, and Linux.   Compass was initially developed by Andrew Collette, a Research Scientist with IMPACT (Institute for Modeling Plasma, Atmospheres and Cosmic Dust).  He has decided to work with The HDF Group to further the development of Compass. Andrew has written a very interesting blog that goes into some of the background of Compass and...

* With Python’s Help

Gerd Heber, The HDF Group

Before the recent release of our PyHexad Excel add-in for HDF5[1], the title might have sounded like the slogan of a global coffee and baked goods chain. That was then. Today, it is an expression of hope for the spreadsheet users who run this country and who either felt neglected by the HDF5 community or who might suffer from a medical condition known as data-bulging workbook stress disorder. In this article, I would like to give you a quick overview of the novel PyHexad therapy and invite you to get involved (after consulting with your doctor).

To access the data in HDF5 files from Excel is a frontrunner among the all-time TOP 10 most frequently asked for features. A spreadsheet tool might be a convenient window into, and user interface for, certain data stored in HDF5 files. Such a tool could help overcome Excel storage and performance limitations, and allow data to be freely “shuttled” between worksheets and HDF5 data containers. PyHexad ([4],[5],[6],[7]) is an attempt to further explore this concept.