1 / 12

Development of DiFX

Development of DiFX. Adam Deller NRAO 3rd DiFX workshop, Curtin University, Perth. Outline. Reasons for the development of DiFX Development of fxcorr (pre-DiFX) Rationale and planning of DiFX DiFX for the LBA DiFX at NRAO and elsewhere. DiFX: the raison d’etre.

sharonmontgomery
Télécharger la présentation

Development of DiFX

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Development of DiFX Adam Deller NRAO 3rd DiFX workshop, Curtin University, Perth

  2. Outline • Reasons for the development of DiFX • Development of fxcorr (pre-DiFX) • Rationale and planning of DiFX • DiFX for the LBA • DiFX at NRAO and elsewhere 3rd DiFX workshop, Curtin University, Perth

  3. DiFX: the raison d’etre • In 2004, the LBA installed new disk-based recorders capable of 4x the bandwidth of the S2 tape system • The existing hardware correlator could not interface to the new recorders • Required: a “stop-gap” solution before the CABB correlator for ATCA was ready for VLBI data The S2 correlator 3rd DiFX workshop, Curtin University, Perth

  4. DiFX: the raison d’etre 3rd DiFX workshop, Curtin University, Perth

  5. 2005: Development of fxcorr • My PhD began February 2005 - first attempt was FX-style correlator which ran on a single node (distribution via scripts/data division) • Naivete in both C++ and correlators led me to build in some idiosyncracies/inefficiencies • Verified against S2 results, but plans made to redesign from scratch, using data distribution with MPI - mpifxcorr, copy/pasting the internals of the correlation code 3rd DiFX workshop, Curtin University, Perth

  6. Rationale/planning of DiFX • At this stage, plans made to support other formats than LBA (specifically Mark5) • Attempted to not “design out” any general applications, but the main focus was nevertheless on LBA operations • Also made provisions from the outset for eVLBI connections into the correlator • Main development was complete by mid 2006 3rd DiFX workshop, Curtin University, Perth

  7. DiFX at the LBA • DiFX has been the production correlator of the LBA since end of 2006 • Plans to use the CABB correlator as the LBA correlator have been shelved • 2008: Correlation moves from Swinburne to Curtin • Oversubscription rate has risen substantially since DiFX + LBADR (recorders) introduced - maybe ~1.5 to ~3?? 3rd DiFX workshop, Curtin University, Perth

  8. Science highlights at the LBA • First trans-Tasman fringes - to a 6m dish in NZ! 3rd DiFX workshop, Curtin University, Perth

  9. Science highlights at the LBA • First trans-Tasman fringes - to a 6m dish in NZ! • First southern hemisphere eVLBI, detecting a flare in Circinus X1 3rd DiFX workshop, Curtin University, Perth

  10. Science highlights at the LBA • First trans-Tasman fringes - to a 6m dish in NZ! • First southern hemisphere eVLBI, detecting a flare in Circinus X1 • 6 new pulsar parallaxes, trebling the number of Southern pulsar parallaxes 3rd DiFX workshop, Curtin University, Perth

  11. DiFX at the VLBA • VLBA sensitivity upgrade has been an ongoing project that requires a new correlator to deal with increased data rates • DiFX selected in 2008 • Going “live” this proposal cycle - first element of the upgrade (backends and recorders to come) to do so • Huge amounts of streamlining and infrastructure have been contributed by the NRAO efforts 3rd DiFX workshop, Curtin University, Perth

  12. DiFX worldwide • DiFX is likely to replace three other existing hardware correlators: Bonn, USNO, Haystack • This is the third DiFX workshop - attendance has gone from about 8 to about 12 to about 24 - the last year especially has been an exciting time development- and adoption-wise • Lets keep this thing rolling! 3rd DiFX workshop, Curtin University, Perth

More Related