On Mon, 2008-01-28 at 11:22 -0600, James Richardson wrote:
> Ian,
> 
> I do not have my test results in front of me at the moment, so I'll
> assume you are correct. Regardless though; there is still a noticeable
> 'slow down' when using a RR set with a large number of hosts. Due to the
> number of rpc pings it must do to each address in the RR set (or could
> be something totally different).

I wouldn't know as you didn't include any time info after trying the
patch containing the work I did to remove the extra name name lookups.

> 
> I know for my particular application we would like autofs to just grab
> the 1st address from the result set and trust that the returned order is
> randomized appropriately.
> 
> Thanks,
> 
> ---
> James T. Richardson, Jr.
> [EMAIL PROTECTED]
> eXcellence in IS Solutions, Inc.
> 713-862-9200 x226
> 
> Making IT Work for You
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> 
> -----Original Message-----
> From: Ian Kent [mailto:[EMAIL PROTECTED] 
> Sent: Monday, January 28, 2008 10:11 AM
> To: James Richardson
> Cc: [email protected]
> Subject: RE: [autofs] Slow mounts when using large round robin sets
> 
> 
> On Mon, 2008-01-28 at 10:07 -0600, James Richardson wrote:
> > Ian,
> > 
> > My apologizes for the delayed response in this; the e-mail never came
> > into my inbox for some reason.
> > 
> > The last patch you sent showed that there were multiple DNS queries
> made
> > for the same target host - not a query.
> 
> No it didn't.
> It did exactly one query.
> 
> > 
> > Also, you had said that for each host in a round-robin set autofs will
> > perform an RPC ping and choose an appropriate host to connect to. I
> > would actually like a feature to disable all of this logic? Currently
> it
> > would be most useful for my purposes if autofs always used the first
> > address returned from a DNS RR query.
> > 
> > Thanks, 
> > 
> > ---
> > James T. Richardson, Jr.
> > [EMAIL PROTECTED]
> > eXcellence in IS Solutions, Inc.
> > 713-862-9200 x226
> > 
> > Making IT Work for You
> > HPC & Enterprise IT Solutions
> > * HPC Application Acceleration
> > * Cluster Design, Deploy, Manage, Train
> > * Linux/Windows Integration
> > * Remote Management, Backup, Anti-Spam/Virus
> > * Network Assessments, Design
> > * Security Audits, Design
> > * Datacenter Design, Relocation
> > * Messaging and Collaboration
> > 
> > 
> > ----- Original Message -----
> > 
> > On Tue, 2008-01-15 at 14:04 -0600, James Richardson wrote:
> > > Ian,
> > > 
> > > Would you recommend an alternative method? Having this would fix a
> > > -really- large pain of mine.
> > 
> > Sorry, I've lost the context of this thread with this top posting.
> > But I'll have a try at a reply.
> > 
> > What behavior do you need?
> > You never really gave any useful comments on the last patch I sent,
> > except the output, which indicated that only one DNS lookup was being
> > performed, and I thought that was your concern, is that right or has
> > what you need changed?
> > 
> > > 
> > > Thanks,
> > > 
> > > ---
> > > James T. Richardson, Jr.
> > > [EMAIL PROTECTED]
> > > eXcellence in IS Solutions, Inc.
> > > 713-862-9200 x226
> > > 
> > > Making IT Work for You
> > > HPC & Enterprise IT Solutions
> > > * HPC Application Acceleration
> > > * Cluster Design, Deploy, Manage, Train
> > > * Linux/Windows Integration
> > > * Remote Management, Backup, Anti-Spam/Virus
> > > * Network Assessments, Design
> > > * Security Audits, Design
> > > * Datacenter Design, Relocation
> > > * Messaging and Collaboration
> > > 
> > > 
> > > -----Original Message-----
> > > From: [EMAIL PROTECTED]
> > > [mailto:[EMAIL PROTECTED] On Behalf Of James
> Richardson
> > > Sent: Wednesday, January 09, 2008 12:11 PM
> > > To: Ian Kent
> > > Cc: [email protected]
> > > Subject: Re: [autofs] Slow mounts when using large round robin sets
> > > Importance: High
> > > 
> > > Ian,
> > > 
> > > For my particular application it would be best to always have AutoFS
> > use
> > > the first address returned from a round robin set. That being said,
> I
> > > can also envision scenarios where the current implementation would
> be
> > > useful.
> > > 
> > > Since both situations need to be supported, I propose the addition
> of
> > a
> > > flag variable: (for example) CHECK_MULTIPLE_RESULTSET= [ none |
> > > proximity ]. When none is set, it just uses the first address
> > returned.
> > > If multiple addresses are returned and 'proximity' is set, AutoFS
> > could
> > > then validate each address in the return set using the proximity
> logic
> > > currently in place.
> > > 
> > > If you would like, I can work on adding support for adding this
> > feature
> > > so that you can review and include it. Do you have any
> recommendations
> > > on methods for implementing this?
> > > 
> > > ---
> > > James T. Richardson, Jr.
> > > [EMAIL PROTECTED]
> > > eXcellence in IS Solutions, Inc.
> > > 713-862-9200 x226
> > > 
> > > Making IT Work for You
> > > HPC & Enterprise IT Solutions
> > > * HPC Application Acceleration
> > > * Cluster Design, Deploy, Manage, Train
> > > * Linux/Windows Integration
> > > * Remote Management, Backup, Anti-Spam/Virus
> > > * Network Assessments, Design
> > > * Security Audits, Design
> > > * Datacenter Design, Relocation
> > > * Messaging and Collaboration
> > > 
> > > 
> > > -----Original Message-----
> > > From: [EMAIL PROTECTED]
> > > [mailto:[EMAIL PROTECTED] On Behalf Of Ian Kent
> > > Sent: Wednesday, January 02, 2008 7:34 PM
> > > To: Steve Thompson
> > > Cc: [email protected]
> > > Subject: Re: [autofs] Slow mounts when using large round robin sets
> > > 
> > > On Wed, 2008-01-02 at 17:43 -0500, Steve Thompson wrote:
> > > > On Wed, 2 Jan 2008, Ian Kent wrote:
> > > > 
> > > > > But, when multiple addresses are returned, autofs uses them as
> > > though
> > > > > they were multiple names and checks to see if they are up and
> what
> > > the
> > > > > response to an NULL procedure ping is so it can put them in
> least
> > > loaded
> > > > > order, assuming the servers are at the same proximity.
> > > > 
> > > > How about dividing those IP addresses into two sets: those on the
> > same
> > > > subnet as the client and those that aren't, and then proceding as
> > > > above? That might save a hop or two for "close" clients.
> > > 
> > > >From the comment in modules/replicated.c (including spelling
> > mistakes):
> > > 
> > > A priority ordered list of hosts is created by using the following
> > > selection rules.
> > > 
> > >    1) Highest priority in selection is proximity.
> > >       Proximity, in order of precedence is:
> > >         - PROXIMITY_LOCAL, host corresponds to a local interface.
> > >         - PROXIMITY_SUBNET, host is located in a subnet reachable
> > >           through a local interface.
> > >         - PROXIMITY_NETWORK, host is located in a network reachable
> > >           through a local interface.
> > >         - PROXIMITY_OTHER, host is on a network not directlty
> > >           reachable through a local interface.
> > > 
> > >    2) NFS version and protocol is selected by caclculating the
> largest
> > >       number of hosts supporting an NFS version and protocol that
> > >       have the closest proximity. These hosts are added to the list
> > >       in response time order. Hosts may have a corresponding weight
> > >       which essentially increaes response time and so influences the
> > >       host order.
> > > 
> > >    3) Hosts at further proximity that support the selected NFS
> version
> > >       and protocol are also added to the list in response time order
> > as
> > >       in 2 above.
> > > 
> > > At least that's how I think it works and hopefully I haven't changed
> > > that with subsequent changes.
> > > 
> > > Ian
> > > 
> > > 
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> > > 
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> > 
> > 
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> > 
> > 
> 
> 
> NOTICE:
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