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Title: Asymptotically Optimal Load Balancing in Large-scale Heterogeneous Systems with Multiple Dispatchers
We consider the load balancing problem in large-scale heterogeneous systems with multiple dispatchers. We introduce a general framework called Local-Estimation-Driven (LED). Under this framework, each dispatcher keeps local (possibly outdated) estimates of the queue lengths for all the servers, and the dispatching decision is made purely based on these local estimates. The local estimates are updated via infrequent communications between dispatchers and servers. We derive sufficient conditions for LED policies to achieve throughput optimality and delay optimality in heavy-traffic, respectively. These conditions directly imply delay optimality for many previous local-memory based policies in heavy traffic. Moreover, the results enable us to design new delay optimal policies for heterogeneous systems with multiple dispatchers. Finally, the heavy-traffic delay optimality of the LED framework also sheds light on a recent open question on how to design optimal load balancing schemes using delayed information.  more » « less
Award ID(s):
1901057
PAR ID:
10293831
Author(s) / Creator(s):
; ;
Date Published:
Journal Name:
ACM SIGMETRICS Performance Evaluation Review
Volume:
48
Issue:
3
ISSN:
0163-5999
Page Range / eLocation ID:
57 to 58
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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