Bug 1282826

Summary: hackbench: modify to run within NUMA node to avoid cross-node traffic
Product: Red Hat Enterprise Linux 7 Reporter: Clark Williams <williams>
Component: rtevalAssignee: Clark Williams <williams>
Status: CLOSED ERRATA QA Contact: Jiri Kastner <jkastner>
Severity: high Docs Contact:
Priority: high    
Version: 7.3CC: bhu, jkastner, kzhang, lmiksik
Target Milestone: rcKeywords: ZStream
Target Release: 7.3   
Hardware: x86_64   
OS: Linux   
Whiteboard:
Fixed In Version: Doc Type: No Doc Update
Doc Text:
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 Story Points: ---
Clone Of:
: 1284553 1284980 (view as bug list) Environment:
Last Closed: 2016-11-04 01:34:16 UTC Type: Bug
Regression: --- Mount Type: ---
Documentation: --- CRM:
Verified Versions: Category: ---
oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
Cloudforms Team: --- Target Upstream Version:
Embargoed:
Bug Depends On:    
Bug Blocks: 1274397, 1282922, 1284553, 1284980    
Attachments:
Description Flags
patch to prevent hackbench generating cross-numa-node traffic none

Description Clark Williams 2015-11-17 14:39:09 UTC 
the hackbench load excercises memory allocation/free and memory copies. Originally rteval started it's loads across the entire set of cpus, but this is not consistent with good RT programming practice as it generates large amounts of cross-node memory traffic, which leads to latency spikes. 

Modify hackbench to run one instance for each numa node in the system, rather than one instance for the entire system.
Comment 1 Clark Williams 2015-11-17 22:33:33 UTC 
Created attachment 1095714 [details]
patch to prevent hackbench generating cross-numa-node traffic
Comment 6 errata-xmlrpc 2016-11-04 01:34:16 UTC 
Since the problem described in this bug report should be
resolved in a recent advisory, it has been closed with a
resolution of ERRATA.

For information on the advisory, and where to find the updated
files, follow the link below.

If the solution does not work for you, open a new bug report.

https://rhn.redhat.com/errata/RHBA-2016-2244.html