NetBSD Problem Report #49450

From dholland@macaran.localdomain  Thu Dec  4 20:56:54 2014
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Message-Id: <20141204205713.650D66E260@macaran.localdomain>
Date: Thu,  4 Dec 2014 15:57:13 -0500 (EST)
From: dholland@eecs.harvard.edu
Reply-To: dholland@eecs.harvard.edu
To: gnats-bugs@NetBSD.org
Subject: make doesn't know about processor cache affinity
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>Number:         49450
>Category:       bin
>Synopsis:       make doesn't know about processor cache affinity
>Confidential:   no
>Severity:       serious
>Priority:       medium
>Responsible:    bin-bug-people
>State:          open
>Class:          change-request
>Submitter-Id:   net
>Arrival-Date:   Thu Dec 04 21:00:00 +0000 2014
>Originator:     David A. Holland
>Release:        NetBSD 7.99.1 (20140819)
>Organization:
>Environment:
System: NetBSD macaran 7.99.1 NetBSD 7.99.1 (MACARAN) #22: Fri Oct 24 18:32:54 EDT 2014 dholland@macaran:/usr/src/sys/arch/amd64/compile/MACARAN amd64
Architecture: x86_64
Machine: amd64
>Description:

When running in parallel, make doesn't know about processor cache
affinity; when there's something to run, it always picks the next
available worker regardless of context.

This probably doesn't matter that much for the average build (as
compiles don't have that much shared state) but it can matter a lot if
you're using make for parallel data processing. As that's not
uncommon, it's an issue that make should take some account of.

>How-To-Repeat:

>Fix:
HACKEM MUCHE

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