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Showing posts from August, 2017

ACAT 2017

The 18th International Workshop on Advanced Computing and Analysis Techniques in Physics Research (ACAT) took place in Seattle this week. We presented our work on integrating the dynamic web federation into HEP computing as a poster.

The conference focused on the use of machine learning algorithm in physics research with contributions from industry offering effective computing technology to execute workflows employing deep neural nets.

These technologies offer solutions to the computing issues the field is facing in light of a great increase in data with a constant computing budget. When the LHC experiments were planned it was assumed that Dennard Scaling would solve this problem for us, it has become clear that this is not the case.

It was shown that generative adversarial neural nets may be used to do do simulation, and that supervised learning may provide options for triggering and reconstruction. In some places these technologies are already used. nVidia, Microsoft, and DWave pres…

Glint Version 2 Enters Production

After several months of prototyping and development Glint version 2.0 (Glint v2) has entered production. Glint v2 is a standalone web service inspired by Colin Leavett-Brown and Ron Desmarais' original glint service (Glint v1). The idea of glint was to allow for image replication across multiple openstack clouds using a simple interface instead of manually downloading and uploading images to new locations. Version 2 differs from the original in that it is a dedicated web service instead of an extension of the Openstack Horizon dashboard. Unfortunately the Openstack developers had a different philosophy regarding image and repository management and decided not to accept glint v1 as a proprietary module.

The Openstack 6 month development cycle made it unreasonable for a small group like UVic's HEPRC group to maintain Glint v1 as an openstack plugin. Instead a new version of the service was concei…

Authorization in DynaFed, Part 2

As we showed previously, there is an easy way to use the information derived from VOMS-server based on grid-mapfiles to authorize a specific user to access a specific part of the dynamic federation. This solution was based on 3 parts:

a grid-mapfile listing the DNs of all users from all supported VOs with all possible rolesa text file (accessfile) that specifies the different privileges for the different parts of the storage federationa python script that is doing the authentication and authorization based on the 2 previously mentioned files While in this solution the grid-mapfile and accessfile can be changed anytime without the need to reload/restart the httpd and memcache process, there is also a simpler solution based on the internal authentication methods possible which however needs to restart httpd and memcache after each change. This one will be explained in the following.


Using the built in authentication in Dynafed, one can grant access to a specific part of the federation to…