Arnold Rosenberg, post-retirement

Distinguished University Professor Emeritus Arnold (Arny) Rosenberg retired from UMass Amherst CS in 2007, but that does not mean that he has slowed down in private life or in research. This year, he and his wife Susan celebrated 50 years of marriage, he ran the Falmouth Road Race, he sang with the Kingston Trio cover band, he has an upcoming paper at the 2014 Euro-Par conference that is a counter-balance to his 1964 paper at the IEEE conference that evolved into FOCS (IEEE Symposium on Foundations of Computer Science), and he received the Outstanding Service Award from IEEE/CS TCPP.

Throughout his career, Rosenberg has been a theoretical computer scientist/engineer. He has worked in almost every branch of theoretical computer science, with a multi-decade concentration on a range of issues relating to what is commonly termed "parallel and distributed computing." His career began with 16 years at the IBM Research Center in Yorktown Heights, NY. "It was a magical place in those days, where I rubbed shoulders with the likes of Michael Rabin, Benoit Mandelbrot, and Dick Karp," notes Rosenberg. He then moved into academia for 26 years, mostly at UMass Amherst, after a short experiment at Duke. His latest endeavors involve research professorships, first at Colorado State, and now at Northeastern.

His research life has intensified once again, mirroring his time at IBM. He has participated in three multi-person research grants since retirement, his first since IBM. He currently works on these projects:

*    a solo (unsupported) study of finite-state robots [shades of 1964!, notes Rosenberg];
*    a quest for high performance computing in "dynamically heterogeneous" environments such as clouds, in collaboration with Rajmohan Rajaraman (Northeastern) and Michela Taufer (U. Delaware);
*    an education-oriented project focusing on parallel and distributed computing (PDC), which is embodied in the CDER Center for Curriculum Development and Educational Resources. He co-directs this effort with Sushil Prasad (GSU, the PI), Anshul Gupta (IBM), Alan Sussman (UMd), and Chip Weems (UMass Amherst).

Rosenberg's study of finite-state robots seeks scalable provably efficient algorithms for a variety of path-planning and exploration problems. "As usual, the problems that I study are idealized versions of problems studied by 'real' roboticists," says Rosenberg.

His primary research focus is the scheduling study, joint research with Rajaraman and Taufer, along with former postdoc Trilce Estrada (UNM) and students. This research extends earlier work on the same problem, with Gennaro Cordasco (Naples) and Greg Malewicz (Google). The basic question is, "How does one achieve high performance when computing in an environment about which one has no reliable performance information?" This study arose from a conversation with Fran Berman (RPI) after she gave a distinguished lecture at UMass Amherst. His response to this question was the IC-scheduling paradigm that he studied for several years, which has evolved into the AREA-oriented scheduling paradigm that is his main focus now. "Extensive simulations suggest that the purely mathematical/algorithmic setting of AREA-oriented scheduling does, indeed, enhance the likelihood of efficient performance in dynamically heterogeneous environments," notes Rosenberg. "Thus far, we have tested our schedules on primitive simulators of such environments. Taufer and Estrada are developing sophisticated simulators that will take us to the next stage of our work."

The CDER Center grew out of a task force supported by NSF and IEEE/CS/TCPP, which was charged with developing guidelines for incorporating material about PDC throughout undergraduate CS/CE curricula. Under Prasad's leadership, the Center now: (a) runs educational workshops at research conferences (most notably the EDUPAR Workshop at IPDPS), (b) collects and sponsors the development of educational resources; (c) runs the Early Adopter Program, under which more than 100 institutions of various levels worldwide are incorporating PDC into their curricula; and (d) is assembling a leading-edge computing cluster that will be dedicated 100% to undergraduate education and research activities. Rosenberg is gratified to see an international community building around the CDER Center's efforts.

"I thought that I was going to spend my retirement years writing poetry and contemplating the grandeur of Vineyard Sound," says Rosenberg. "Instead, I find myself busier and more fulfilled than ever. Thankfully, I am still able to nurture my love of singing and jogging, but I am doing that with the comforting knowledge that 'the juices are still flowing'."