2026-07-24T12:23:44Z https://drops.dagstuhl.de/oai

oai:drops-oai.dagstuhl.de:11148 2024-03-06T10:47:33Z ddc:004 open_access

Simpler and Better Algorithms for Minimum-Norm Load Balancing Chakrabarty, Deeparnab Swamy, Chaitanya Approximation Algorithms Recently, Chakrabarty and Swamy (STOC 2019) introduced the minimum-norm load-balancing problem on unrelated machines, wherein we are given a set J of jobs that need to be scheduled on a set of m unrelated machines, and a monotone, symmetric norm; We seek an assignment sigma: J -> [m] that minimizes the norm of the resulting load vector load_{sigma} in R_+^m, where load_{sigma}(i) is the load on machine i under the assignment sigma. Besides capturing all l_p norms, symmetric norms also capture other norms of interest including top-l norms, and ordered norms. Chakrabarty and Swamy (STOC 2019) give a (38+epsilon)-approximation algorithm for this problem via a general framework they develop for minimum-norm optimization that proceeds by first carefully reducing this problem (in a series of steps) to a problem called min-max ordered load balancing, and then devising a so-called deterministic oblivious LP-rounding algorithm for ordered load balancing. We give a direct, and simple 4+epsilon-approximation algorithm for the minimum-norm load balancing based on rounding a (near-optimal) solution to a novel convex-programming relaxation for the problem. Whereas the natural convex program encoding minimum-norm load balancing problem has a large non-constant integrality gap, we show that this issue can be remedied by including a key constraint that bounds the "norm of the job-cost vector." Our techniques also yield a (essentially) 4-approximation for: (a) multi-norm load balancing, wherein we are given multiple monotone symmetric norms, and we seek an assignment respecting a given budget for each norm; (b) the best simultaneous approximation factor achievable for all symmetric norms for a given instance. Schloss Dagstuhl – Leibniz-Zentrum für Informatik Deeparnab Chakrabarty and Chaitanya Swamy 2019 Is Part Of LIPIcs, Volume 144, 27th Annual European Symposium on Algorithms (ESA 2019) InProceedings Text doc-type:ResearchArticle publishedVersion application/pdf doi:10.4230/LIPIcs.ESA.2019.27 urn:nbn:de:0030-drops-111488 https://drops.dagstuhl.de/entities/document/10.4230/LIPIcs.ESA.2019.27 eng https://creativecommons.org/licenses/by/3.0/legalcode