Bug 639803

Summary: Performance Tuning Guide: TRACKING BUG for [Network] [The Multicast Problem]
Product: Red Hat Enterprise Linux 6 Reporter: Don Domingo <ddomingo>
Component: doc-Performance_Tuning_GuideAssignee: Laura Bailey <lbailey>
Status: CLOSED CURRENTRELEASE QA Contact: ecs-bugs
Severity: medium Docs Contact:
Priority: low    
Version: 6.1CC: nhorman
Target Milestone: rcKeywords: Documentation, Tracking
Target Release: ---   
Hardware: All   
OS: Linux   
Whiteboard:
Fixed In Version: 6.1 Doc Type: Bug Fix
Doc Text:
Story Points: ---
Clone Of: Environment:
Last Closed: 2011-07-04 01:52:12 UTC Type: ---
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: 639779    

Comment 7 Neil Horman 2011-02-15 17:25:23 UTC
Thanks, Don the content looks good, 1 request though: Could we please change the heading of the section to something other than "The Multicast Problem".  I know I described it as such in my writing to you, but it reads like we're shipping known defects when I see it in print for customer consumables.  Perhaps something more neutral, like "multicast performance", or "Multicast considerations"?

In answer to your questions, yo udistinguish which technique mitigates multicast performance the same way you do any other performance problem: By first looking at the metrics you've outlined in other sections and observing where frames are dropping.  The kernel doesn't care that its muticast traffic, its just dropping frames, and based on the location, you can take action to mitigate that.

In regards to your last sentence, I think its good, but It would be more correct to say:
...Alternatively, you can try optimizing applications use of a socket.."

Its the application that uses a socket, not a socket that uses an application.

Comment 8 Don Domingo 2011-02-15 23:38:27 UTC
(In reply to comment #7)
> Thanks, Don the content looks good, 1 request though: Could we please change
> the heading of the section to something other than "The Multicast Problem".  I
> know I described it as such in my writing to you, but it reads like we're
> shipping known defects when I see it in print for customer consumables. 
> Perhaps something more neutral, like "multicast performance", or "Multicast
> considerations"?
> 

you're right. Multicast Considerations sounds much better. revised as such.h

> In answer to your questions, yo udistinguish which technique mitigates
> multicast performance the same way you do any other performance problem: By
> first looking at the metrics you've outlined in other sections and observing
> where frames are dropping.  The kernel doesn't care that its muticast traffic,
> its just dropping frames, and based on the location, you can take action to
> mitigate that.
> 

ok

> In regards to your last sentence, I think its good, but It would be more
> correct to say:
> ...Alternatively, you can try optimizing applications use of a socket.."
> 
> Its the application that uses a socket, not a socket that uses an application.

thanks, revised as:
<new>
Alternatively, you can try optimizing an application's socket use; to do so, configure the application to control a single socket and disseminate the received network data quickly to other user-space processes.
</new>

setting this bug now to MODIFIED. thanks again, Neil!

Comment 11 Michael Doyle 2011-05-06 04:19:57 UTC
Verified in Red_Hat_Enterprise_Linux-Performance_Tuning_Guide-6-en-US-1.0-28