All of lore.kernel.org
 help / color / mirror / Atom feed
From: "Bryn M. Reeves" <bmr@redhat.com>
To: sekharan@linux.vnet.ibm.com,
	device-mapper development <dm-devel@redhat.com>
Subject: Re: multipath.conf and polling_interval option seems	misleading
Date: Fri, 16 Jan 2009 16:13:12 +0000	[thread overview]
Message-ID: <4970B218.7090306@redhat.com> (raw)
In-Reply-To: <1232122255.29644.23.camel@chandra-ubuntu>

Chandra Seetharaman wrote:
>> The behaviour I seen in RHEL4 and RHEL5 was working as design after
>> reviewing the code and talking to a couple engineers.
>>
>> The problem it seems is how I was reading the description of the option.
>>  From my results in testing and talking with some engineers the 
>> "polling_interval" option actually means:
>>
>> "The interval between checking all possible paths for all multipath paths"
>> ----------
>>
>> 1) Is my assumption correct that "polling_interval" actually means:
>> "The interval between checking all possible paths for all multipath paths"
>>
>> 2) What is a better way to describe the "polling_interval" option?
>>
>> 3) Shouldn't we make it clearer for people who don't that that much 
>> experience with multipathing?
> 
> IMO, the behavior seen is the proper behavior.
> 
> If it does as per your interpretation, the seconds between checking of
> the same path will depend on the number of paths to a storage, which may
> not be acceptable.
> 
> May be the wording in multipath.conf.annotated should be made clear.

Agreed - I'd not even really thought about this until Shane brought it 
up as I'd read the description to mean exactly what the code does.

It does seem that some users are puzzled by this behaviour - can't 
hurt to make the wording a little more explicit for this option.

Regards,
Bryn.

  reply	other threads:[~2009-01-16 16:13 UTC|newest]

Thread overview: 7+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2009-01-16 16:03 multipath.conf and polling_interval option seems misleading shane bradley
2009-01-16 16:10 ` Chandra Seetharaman
2009-01-16 16:13   ` Bryn M. Reeves [this message]
2009-01-16 18:34     ` Chandra Seetharaman
2009-01-16 16:21   ` shane bradley
2009-01-29 16:21     ` shane bradley
2009-01-29 16:44       ` Bryn M. Reeves

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=4970B218.7090306@redhat.com \
    --to=bmr@redhat.com \
    --cc=dm-devel@redhat.com \
    --cc=sekharan@linux.vnet.ibm.com \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.