Subject: [xmpp] #21: recommended frequency of keepalives

From: "xmpp issue tracker" <[email-masked]>
Date: Mon, 14 Jun 2010 20:48:09 -0000

#21: recommended frequency of keepalives
--------------------------------+-------------------------------------------
 Reporter:  stpeter@…           |       Owner:  stpeter@…         
     Type:  defect              |      Status:  new               
 Priority:  minor               |   Milestone:                    
Component:  3920bis             |     Version:                    
 Severity:  In WG Last Call     |    Keywords:                    
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 Section 4.3.3 (Handling of Idle Streams) states:

 > however, it is RECOMMENDED that any such test be performed
 > not more than once every 60 seconds.

 Ben Campbell commented: "Does it make sense to recommend the same for all
 types of keepalives? Every 60 seconds could be quite a lot for a heavier
 weight transaction response mechanism. Also, do any of the referenced docs
 offer guidance on selecting the mechanisms?"

 Dave Cridland commented: "the recommendations I'm hearing seem to be that
 servers should be very conservative in doing whitespace pings - ie, every
 5 minutes or more."

-- 
Ticket URL: <http://tools.ietf.org/wg/xmpp/trac/ticket/21>
xmpp <http://tools.ietf.org/xmpp/>

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From: Peter Saint-Andre <[email-masked]>
Date: Thu, 24 Jun 2010 21:57:55 -0600

On 6/14/10 2:48 PM, xmpp issue tracker wrote:
>  types of keepalives? 

I don't think we are. We're simply saying "don't do this more than once
a minute".

>  Every 60 seconds could be quite a lot for a heavier
>  weight transaction response mechanism. 

True. Whitespace keepalizes are not heavy, though.

>  Also, do any of the referenced docs

No.

>  servers should be very conservative in doing whitespace pings - ie, every

Dave, are you suggesting that we change the text to the following?

   it is RECOMMENDED that any such test be performed
   not more than once every 5 minutes.

Peter

-- 
Peter Saint-Andre
https://stpeter.im/

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From: Dave Cridland <[email-masked]>
Date: Fri, 25 Jun 2010 11:23:09 +0100

>    not more than once every 5 minutes.

I think this is a case where the recommended timings will vary  
strongly over time.

5 minutes feels very long to be - that said, this is what I'm told by  
mobile people, and moreover mobile people are recommending that  
keepalives should be send only by the client, to allow them to send  
them when the radio is up, or when keepalives for other sessions and  
protocols need to be sent.

I would therefore use text something like:

"At the time of writing, it is RECOMMENDED that any such test be  
performed not more than once every 5 minutes, and ideally clients,  
rather than servers, should perform these checks. Implementors are  
encouraged to seek additional advice, particularly in mobile and  
other power-constrained environments."

---

From: Peter Saint-Andre <[email-masked]>
Date: Sun, 27 Jun 2010 14:25:53 -0600

On 6/25/10 4:23 AM, Dave Cridland wrote:
> I think this is a case where the recommended timings will vary strongly
> over time.
> 
> keepalives should be send only by the client, to allow them to send them
> when the radio is up, or when keepalives for other sessions and
> encouraged to seek additional advice, particularly in mobile and other
> power-constrained environments."

Good suggestion. I now have:

###

   Implementers are advised to support whichever
   connection-testing methods they deem appropriate, but to carefully
   weigh the network impact of such methods against the benefits of
   discovering idle streams in a timely manner.  The length of time
   between the use of any particular connection test is very much a
   matter of local service policy and depends strongly on the network
   environment and usage scenarios of a given deployment and connection
   type; at the time of writing, it is RECOMMENDED that any such test be
   performed not more than once every 5 minutes and that, ideally, such
   checks will be initiated by clients rather than servers.  Those who
   implement XMPP software and deploy XMPP services are encouraged to
   seek additional advice regarding appropriate timing of stream-level
   keepalives, particularly when power-constrained devices are used
   (e.g., in mobile environments).

###

Peter

-- 
Peter Saint-Andre
https://stpeter.im/

---

From: "xmpp issue tracker" <[email-masked]>
Date: Sun, 27 Jun 2010 22:06:13 -0000

#21: recommended frequency of keepalives
--------------------------------+-------------------------------------------
 Reporter:  stpeter@…           |        Owner:  stpeter@…         
     Type:  defect              |       Status:  closed            
 Priority:  minor               |    Milestone:                    
Component:  3920bis             |      Version:                    
 Severity:  In WG Last Call     |   Resolution:  fixed             
 Keywords:                      |  
--------------------------------+-------------------------------------------
Changes (by stpeter@…):

  * status:  new => closed
  * resolution:  => fixed

Comment:

 See list discussion for resolution.

-- 
Ticket URL: <https://trac.tools.ietf.org/wg/xmpp/trac/ticket/21#comment:1>
xmpp <http://tools.ietf.org/xmpp/>