open source Tag

Dave Pearah, The HDF Group In my previous post—HDF: The Next 30 Years (Part 1)—I outlined the challenges and opportunities facing The HDF Group as an open source company. In a nutshell: Opportunity: large-scale adoption around the world in many different industries with great community-driven development (700+ projects in Github) Challenge: sufficient profit from existing business (consulting) to sustainably extend and maintain the core HDF5 platform The HDF Group is blessed with an amazingly talented + passionate + dedicated team of folks who care deeply about the HDF community, and we're all working together to determine the best path forward to sustainability, i.e. the NEXT 30 years. We want to share some of the steps that we're already taking, and -- more importantly --...

Dave Pearah, The HDF Group How can users of open source technology ensure that the open source solutions they depend on every day don’t just survive, but thrive? While on my flight home from New York, I’m reflecting on The Trading Show, which focused on tech solutions for the small but influential world of proprietary and quantitative financial trading. I participated in a panel called “Sharing is Caring,” regarding the industry’s broad use of open source technology. The panel featured a mix of companies that both provide and use open source software. Among the topics: Are cost pressures the only driving force behind the open source movement among trading firms, hedge funds and banks? How will open source solutions shape the future of...

Francesc Alted, Freelance Consultant, HDF guest blogger

The HDF Group has a long history of collaboration with Francesc Alted, creator of PyTables.  Francesc was one of the first HDF5 application developers who successfully employed external compressions in an HDF5 application (PyTables). The first two compression methods that were registered with The HDF Group were LZO and BZIP2 implemented in PyTables; when Blosc was added to PyTables, it became a winner.

While HDF5 and PyTables address data organization and I/O needs for many applications, solutions like the Blosc meta-compressor presented in this blog, are simpler, achieve great I/O performance, and are alternative solutions to HDF5 in cases when portability and data organization are not critical, but compression is still desired.  Enjoy the read!

Why compression?

Compression is a hot topic in data handling. The largest database players have recently (or not-so-recently) implemented support for different kinds of compression libraries. Why is that? It’s all about efficiency: modern CPUs are so fast in comparison with storage write speeds that compression not only offers the opportunity to store more with less space, but to improve storage bandwidth also:

The HDF5 library is an excellent example of a data container that supported out-of-the-box compression in the very first release of HDF5 in November 1998. Their innovation was to introduce support for compression of chunked datasets in a way that permitted the developer to apply compression to each of the chunks individually, resulting in reasonably fast and transparent compression using different codecs. HDF5 also introduced pluggable compression filters that allowed external developers to implement support for different codecs for HDF5. Then with release 1.8.11, they added the ability to discover, load and register filters at run time. More recently, in release 1.8.15 (and fully documented in 1.8.16), HDF5 has a new Plugin Interface that provides a complete programmatic control of dynamically loaded plugins. HDF5’s filter features now offer much-desired flexibility, giving users the freedom to choose the codec that best suits their needs.

Why Blosc?

In the last decade the trend has been to implement faster codecs at the expense of reduced compression ratios. The idea is to reduce compression/decompression time overhead

Lindsay Powers - The HDF Group The HDF Group provides free, open-source software that is widely used in government, academia and industry. The goal of The HDF Group is to ensure the sustainable development of HDF (Hierarchical Data Format) technologies and the ongoing accessibility of HDF-stored data because users and organizations have mission-critical systems and archives relying on these technologies. These users and organizations are a critical element of the HDF community and an important source of new and innovative uses of, and sustainability for, the HDF platforms, libraries and tools. We want to create a sustainability model for the open access platforms and libraries that can serve these diverse communities in the future use and preservation of their data. As a...