Cheng Liao, Margaret Martonosi, and Douglas W. Clark. Experience with an adaptive globally-synchronizing clock algorithm. In Eleventh Annual ACM Symposium on Parallel Algorithms and Architectures (SPAA '99), pages 106--114, New York, June 1999.  Home/Search   Document Details and Download   Summary   Related Articles   Check

....of broadcast media and achieve high precision. However, they cannot synchronize nodes that do not lie within the same broadcast domain. Since our focus here is on global clock synchronization, we don t discuss these more local approaches further. Two global synchronization proposals of note are [11] and [16] The microsecond precision achieved in [11] is similar to our goals here, but the approach assumes a fixed topology and guarantees on latency and determinism in packet delivery. A very energy efficient time diffusion algorithm is presented in [16] but the precision analysis assumes ....

....they cannot synchronize nodes that do not lie within the same broadcast domain. Since our focus here is on global clock synchronization, we don t discuss these more local approaches further. Two global synchronization proposals of note are [11] and [16] The microsecond precision achieved in [11] is similar to our goals here, but the approach assumes a fixed topology and guarantees on latency and determinism in packet delivery. A very energy efficient time diffusion algorithm is presented in [16] but the precision analysis assumes deterministic transmission times. Our interest here is in ....

LIAO, C., MARTONOSI, M., AND CLARK, D. W. Experience with an adaptive globally-synchronizing clock algorithm. In Eleventh Annual ACM Symposium on Parallel Algorithms and Architectures (SPAA '99) (New York, June 1999), pp. 106--114.

....di#cult because of clock drift and non deterministic message delay. Another limiting factor is the amount of communication spent on synchronization. Several probabilistic clock synchronization algorithms have been proposed to achieve a good precision under partially unknown system specifications. [3, 1, 9] use a client server approach to read reference time repeatedly until this succeeds with a specified precision bound. 3] achieves a precision in the order of 1ms using 4 messages per minute, 1] is similar. 9] achieves 1s using highly deterministic Myrinet communication. The drawback of ....

....to achieve a good precision under partially unknown system specifications. 3, 1, 9] use a client server approach to read reference time repeatedly until this succeeds with a specified precision bound. 3] achieves a precision in the order of 1ms using 4 messages per minute, 1] is similar. [9] achieves 1s using highly deterministic Myrinet communication. The drawback of client server schemes is that they do not scale well with system size and synchronization message frequency. A producer consumer approach is taken in [2] With unidirectional communication only, a precision in the order ....

[Article contains additional citation context not shown here]

Cheng Liao, Margaret Martonosi, and Douglas W. Clark. Experience with an adaptive globallysynchronizing clock algorithm. In ACM Symposium on Parallel Algorithms and Architectures, pages 106--114, 1999.

....It is commonly accepted, or assumed, that in general neither of these are particularly reliable for software clocks in PC s. Of the two, the offset has traditionally generated the most concern, and so mechanisms such as the Network Time Protocol (NTP) are widely used to enforce synchronization [1, 8]. However, for network measurement, we point out that it is not offset but the rate characteristics which are of central importance. In this paper we focus on providing a software clock with highly smooth and accurate rate performance, based purely on standard hardware. Our approach is very ....

C. Liao, M.Martonosi, and D.W.Clark. Experience with an adaptive globally synchronizing clock algorithm. In Proc. of 11th ACM Symp. on Parallel Algorithms and Architectures, June 1999.

....we have fully decoupled the sender from the receiver only synchronizing receivers with one another, even when relating the timescale to an external timescale such as UTC. CesiumSpray retains a dependence on the relationship between sender and receiver when synchronizing nodes to UTC. In [18], Liao, et.al. describe a system for synchronizing interfaces on a system area network, Myrinet, with microsecond accuracy. While the precision bounds in this system is similar to ours, their results depend on the use of an underlying network that offers latency and determinism guarantees in fixed ....

C. Liao, M. Martonosi, and D. W. Clark. Experience with an adaptive globally-synchronizing clock algorithm. In Eleventh Annual ACM Symposium on Parallel Algorithms and Architectures (SPAA '99), pages 106--114, New York, June 1999. Association for Computing Machinery.

....NTP [19] stands out by virtue of its scalability, robustness to various types of failures, self configuration, security in the face of deliberate sabotage, and ubiquitous deployment. NTP allows construction of a hierarchy of time servers, multiply rooted at canonical sources of external time. In [16], Liao, et.al. describe a system for synchronizing interfaces on a system area network, Myrinet, with microsecond accuracy. While their precision bound is similar to ours, their results depend on the use of an underlying network that offers latency and determinism guarantees in fixed topologies. ....

Cheng Liao, Margaret Martonosi, and Douglas W. Clark. Experience with an adaptive globally-synchronizing clock algorithm. In Eleventh Annual ACM Symposium on Parallel Algorithms and Architectures (SPAA '99), pages 106--114, New York, June 1999. Association for Computing Machinery.

....The elapsed time of a reference clock is used as the x axis. It can be seen that the accumulated discrepancies increase as the elapsed time increases, regardless of the reference clock. Previous systems have adopted purely software based approaches of varying complexity and accuracy (see [3, 4, 5, 6, 7, 8]) to create a virtual global time out of the individual local clocks available at each node of a distributed system. Some of these approaches, such as the Network Time Protocol [4, 5] are extremely successful in some particular environment (such as the Internet) but not accurate enough to solve ....

....the nested outer states at the beginning of the frame. 4.0 Visualization with Preview and Multiple Views As described in Section1.2, multiple time space diagrams and performance analysis applications may be derived from the same interval trace file. The Argonne visualization tool Jumpshot [7], is modified and used as one viewer. An API to write SLOG (for scalable log file) files is used together with the API described in Section2.4 to read the individual interval files, merge them, and write a file in SLOG format, which is understandable by the Jumpshot tool. In this section we ....

C. Liao et. al. "Experience with an Adaptive Globally-Synchronizing Clock Algorithm, " Proc. of the 11th ACM Symposium on Parallel Algorithms and Architectures, June 1999.

No context found.

Cheng Liao, Margaret Martonosi, and Douglas W. Clark. Experience with an adaptive globally-synchronizing clock algorithm. In Eleventh Annual ACM Symposium on Parallel Algorithms and Architectures (SPAA '99), pages 106--114, New York, June 1999.

No context found.

C. Liao, M. Martonosi, and D. Clark. Experience with an adaptive globally-synchronizing clock algorithm. In Proceedings of the 11th Annual ACM Symposium on Parallel Algorithms and Architectures, pages 106--114, June 1999.

No context found.

Cheng Liao, Margaret Martonosi, and Douglas W. Clark. Experience with an adaptive globally-synchronizing clock algorithm. In ACM SPAA, pages 106--114, New York, June 1999.

No context found.

Cheng Liao, Margaret Martonosi, and Douglas W. Clark. Experience with an adaptive globally-synchronizing clock algorithm. In Eleventh Annual ACM Symposium on Parallel Algorithms and Architectures (SPAA '99), pages 106--114, New York, June 1999.

No context found.

C. Liao, M. Martonosi, and D. Clark. Experience with an adaptive globally-synchronizing clock algorithm. In Proceedings of the 11th Annual ACM Symposium on Parallel Algorithms and Architectures, pages 106--114, June 1999.

No context found.

C. Liao, M. Maronosi, D. Clark, "Experience With an Adaptive Globally-Synchronizing Clock Algorithm," In Eleventh Annual ACM Symposium on Parallel Algorithms and Architectures (SPAA), 1999, pp. 106-114.

No context found.

C. Liao, M. Maronosi, D. Clark: "Experience With an Adaptive Globally-Synchronizing Clock Algorithm", Eleventh Annual ACM Symposium on Parallel Algorithms and Architectures (SPAA), 1999, pp. 106-114.

No context found.

C. Liao, M. Martonosi, and D. Clark. Experience with an adaptive globally-synchronizing clock algorithm. In Proceedings of the 11th Annual ACM Symposium on Parallel Algorithms and Architectures, pages 106--114, June 1999.

No context found.

Cheng Liao, Margaret Martonosi, and Douglas W. Clark. Experience with an adaptive globally-synchronizing clock algorithm. In ACM Symposium on Parallel Algorithms and Architectures, pages 106--114, 1999. 21

Online articles have much greater impact   More about CiteSeer.IST   Add search form to your site   Submit documents   Feedback  

CiteSeer.IST - Copyright Penn State and NEC