Rails - Jan 2007 - Are Mongrel instances "sticky" with respect to sessions?

All,

If you deploy multiple Mongrel instances, is it possible to have
affinity between a given session (e.g. session id) and a Mongrel
instance?  How is that done?

Thanks,
Wes

-- 
Posted via http://www.ruby-forum.com/.

--~--~---------~--~----~------------~-------~--~----~
You received this message because you are subscribed to the Google Groups
"Ruby on Rails: Talk" group.
To post to this group, send email to
rubyonrails-talk-/JYPxA39Uh5TLH3MbocFFw@public.gmane.org
To unsubscribe from this group, send email to
rubyonrails-talk-unsubscribe-/JYPxA39Uh5TLH3MbocFFw@public.gmane.org
For more options, visit this group at
http://groups.google.com/group/rubyonrails-talk?hl=en
-~----------~----~----~----~------~----~------~--~---

On Jan 23, 2007, at 2:06 PM, Wes Gamble wrote:
> If you deploy multiple Mongrel instances, is it possible to have
> affinity between a given session (e.g. session id) and a Mongrel
> instance?  How is that done?
Hello Wes.

Session affinity is generally achieved at the load balancer level,
and Apache 2.2 supports this as well.

See http://httpd.apache.org/docs/2.2/mod/mod_proxy.html and search
locally for lbmethod for details.

Why do you want session affinity? It makes a ton of sense is HUGE
installations, but not so much for smaller ones.

-- 
-- Tom Mornini, CTO
-- Engine Yard, Ruby on Rails Hosting
-- Reliability, Ease of Use, Scalability
-- (866) 518-YARD (9273)


--~--~---------~--~----~------------~-------~--~----~
You received this message because you are subscribed to the Google Groups
"Ruby on Rails: Talk" group.
To post to this group, send email to
rubyonrails-talk-/JYPxA39Uh5TLH3MbocFFw@public.gmane.org
To unsubscribe from this group, send email to
rubyonrails-talk-unsubscribe-/JYPxA39Uh5TLH3MbocFFw@public.gmane.org
For more options, visit this group at
http://groups.google.com/group/rubyonrails-talk?hl=en
-~----------~----~----~----~------~----~------~--~---

> 
> Why do you want session affinity? It makes a ton of sense is HUGE
> installations, but not so much for smaller ones.
> 
Because I ended up having to use a custom in-memory persistence scheme 
to handle objects that were too large to place on the session (and would 
cause Rails to crash during session serialization/deserialization).  So 
I have a hash which stores some larger things (parsed HTML and Excel 
spreadsheet data) that I would like to keep around across requests given 
the relatively high cost of generating them.

If I need to go to two or more Mongrels (which I almost certainly will), 
the hashes will be private to each Mongrel instance (Ruby process) and 
won''t be shared.  Which of course, implies that I might end up 
generating these objects up to N times where N is the number of Mongrel 
instances.

So I would like to either take advantage of session affinity for a given 
Mongrel process to be sure that a given artifact generated on behalf of 
a given user and managed in my hash is only generated once.

If session affinity doesn''t work with Mongrel, then I guess I can look 
into Drb.

Thanks,
Wes

-- 
Posted via http://www.ruby-forum.com/.

--~--~---------~--~----~------------~-------~--~----~
You received this message because you are subscribed to the Google Groups
"Ruby on Rails: Talk" group.
To post to this group, send email to
rubyonrails-talk-/JYPxA39Uh5TLH3MbocFFw@public.gmane.org
To unsubscribe from this group, send email to
rubyonrails-talk-unsubscribe-/JYPxA39Uh5TLH3MbocFFw@public.gmane.org
For more options, visit this group at
http://groups.google.com/group/rubyonrails-talk?hl=en
-~----------~----~----~----~------~----~------~--~---

Tom Mornini wrote:
> Session affinity is generally achieved at the load balancer level,
> and Apache 2.2 supports this as well.
> 
> See http://httpd.apache.org/docs/2.2/mod/mod_proxy.html and search
> locally for lbmethod for details.
Tom,

Thanks.  Just looked at the Apache docs. and I see how this appears to 
be supported.

Wes

-- 
Posted via http://www.ruby-forum.com/.

--~--~---------~--~----~------------~-------~--~----~
You received this message because you are subscribed to the Google Groups
"Ruby on Rails: Talk" group.
To post to this group, send email to
rubyonrails-talk-/JYPxA39Uh5TLH3MbocFFw@public.gmane.org
To unsubscribe from this group, send email to
rubyonrails-talk-unsubscribe-/JYPxA39Uh5TLH3MbocFFw@public.gmane.org
For more options, visit this group at
http://groups.google.com/group/rubyonrails-talk?hl=en
-~----------~----~----~----~------~----~------~--~---

Wes Gamble wrote:
>> Why do you want session affinity? It makes a ton of sense is HUGE
>> installations, but not so much for smaller ones.
>>
> 
> Because I ended up having to use a custom in-memory persistence scheme 
> to handle objects that were too large to place on the session (and would 
> cause Rails to crash during session serialization/deserialization).  So 
> I have a hash which stores some larger things (parsed HTML and Excel 
> spreadsheet data) that I would like to keep around across requests given 
> the relatively high cost of generating them.
> 
...
> If session affinity doesn''t work with Mongrel, then I guess I can
look
> into Drb.
> 
> Thanks,
> Wes
> 
Check out memcached -

http://nubyonrails.com/articles/2006/08/17/memcached-basics-for-rails

sounds like your scheme implements a subset of what memcached already does.

HTH,

-b

--~--~---------~--~----~------------~-------~--~----~
You received this message because you are subscribed to the Google Groups
"Ruby on Rails: Talk" group.
To post to this group, send email to
rubyonrails-talk-/JYPxA39Uh5TLH3MbocFFw@public.gmane.org
To unsubscribe from this group, send email to
rubyonrails-talk-unsubscribe-/JYPxA39Uh5TLH3MbocFFw@public.gmane.org
For more options, visit this group at
http://groups.google.com/group/rubyonrails-talk?hl=en
-~----------~----~----~----~------~----~------~--~---