Abstract

Dynamic resource scheduling is key to achieve dependable service guarantees, allocate spare capacity and protect systems against misuse. For network traffic in a cloud environment, packet scheduling is often done in software, a task made hard by the extremely high frequency of decisions (10+ million packets per second) and the large number of concurrent sources.

No currently available solution simultaneously supports high decision rates, scales to many concurrent clients, and has provable, small deviation from ideal allocation at high link utilization. The pieces to make the above possible do exist, though, from efficient schedulers with tight analytical service guarantees to fast packet I/O frameworks.

In this talk we fill the gap and propose an architecture to run software packet schedulers efficiently even in a high speed, highly concurrent environment. We achieve this result by separating the scheduling decision from the actual packet transmission, so that the latter can be performed in parallel by clients. We provide analytical bounds on the service guarantees of our scheduling architecture even at high link utilization, and present an accurate discussion of implementation issues. Our prototype can make over 20 million scheduling decisions per second even with tens of concurrent clients running on a multi-core, multi-socket system, while adding less than 2 us to the communication delay.

PAPER : http://info.iet.unipi.it/~luigi/research.html#sched16

(Joint work with Paolo Valente, Giuseppe Lettieri, Vincenzo Maffione)

BIO

Luigi Rizzo is a professor at the Universita` di Pisa. He has worked on network emulation, high performance networking, packet scheduling, multicast and reliable multicast. He is a long time contributor to FreeBSD, for which he has developed several subsystems including the dummynet network emulator, the ipfw firewall, and the netmap framework. He has been program committe member for for sigcomm, conext, infocom, nsdi, Usenix ATC , ANCS and other conferences, as well as PC chair for Sigcomm 2009 and Conext 2014, ANCS 2016 , and general chair for Sigcomm 2006. Luigi has been a frequent visiting researcher at various institutions including ICSI /UC Berkeley, Google Mountain View, Intel Research Cambridge, Intel Research Berkeley.