17.04.2015 Views

DARPA ULTRALOG Final Report - Industrial and Manufacturing ...

DARPA ULTRALOG Final Report - Industrial and Manufacturing ...

DARPA ULTRALOG Final Report - Industrial and Manufacturing ...

SHOW MORE
SHOW LESS

You also want an ePaper? Increase the reach of your titles

YUMPU automatically turns print PDFs into web optimized ePapers that Google loves.

Manuscript for IEEE TRANSACTIONS ON PARALLEL AND DISTRIBUTED SYSTEMS 5<br />

The organization of this paper is as follows. In Section 2 we formally define the problem in<br />

detail. After designing the control mechanism in Sections 3 <strong>and</strong> 4, we show empirical results in<br />

Section 5. <strong>Final</strong>ly, we discuss implications <strong>and</strong> possible extensions of our work in Section 6.<br />

2. Problem specification<br />

In this section we formally define the control problem by detailing network configuration <strong>and</strong><br />

control actions. We focus on computational CPU resources assuming that the system is<br />

computation-bounded.<br />

2.1 Network configuration<br />

A network is composed of a set of components A <strong>and</strong> a set of nodes (i.e., machines) N. K n<br />

denotes a set of components that reside in node n sharing the node’s CPU resource. Task flow<br />

structure of the network, which defines precedence relationship between components, is an<br />

arbitrary directed acyclic graph. A problem given to the network is decomposed in terms of root<br />

tasks for some components <strong>and</strong> those tasks are propagated through the task flow structure. Each<br />

component processes one of the tasks in its queue (which has root tasks as well as tasks from<br />

predecessor components) <strong>and</strong> then sends it to successor components. We denote the number of<br />

root tasks of component i as rt i . Fig. 1 shows an example network in which there are four<br />

components residing in three nodes. Components A 1 <strong>and</strong> A 2 reside in N 1 <strong>and</strong> each of them has<br />

100 root tasks. A 3 in N 2 <strong>and</strong> A 4 in N 3 have no root tasks, but they have 200 <strong>and</strong> 100 tasks<br />

respectively from the corresponding predecessors.

Hooray! Your file is uploaded and ready to be published.

Saved successfully!

Ooh no, something went wrong!