RE: single or many haproxy instances

[Justin Franks]

Not sure why you would run multiple HAProxy in one node. I don't understand 
what you want to do. But...

Look into using Consul to help load balance/cluster your HAProxy instances. 
That is what we are doing. Simple and works great. Think of Consul as a Global 
load balancing service that works internally.

Consul will look at all your instances (HAProxy or whatever) and round-robin or 
weight load balance to all of them based on health checks you plug in. I don't 
know if this would solve your prob though.


*
Justin Franks
Lead Operations Engineer
SaaS, Cloud, Data Centers  Infrastructure
Lithium Technologies, Inc
225 Bush St., 15th Floor
San Francisco, CA 94104
tel: +1 415 757 3100 x3219

From: Xu (Simon) Chen xche...@gmail.com
Sent: Monday, June 30, 2014 7:38 AM
To: HAProxy
Subject: single or many haproxy instances

Hi folks,

I am writing a simple load balancer as a service to automate haproxy 
configuration while providing a simple API to users, who only need to give a 
few simple specifications of the load balancer they want.

I am trying to decide whether to run multiple haproxy instances or a single 
instance on a particular node. I currently use jinja2 template to combine all 
services into a single haproxy configuration file and run a single instance of 
haproxy. Every time, when a service spec is changed, I run check config mode, 
and only reload the config if the test passes. But I fear that a single 
incorrect service spec would prevent everyone else from updating their 
services, unless I maintain some last-known good config for every service.

Managing one haproxy instance for every service solves this problem, but I 
might end up with too many processes on a single box.

Any recommendations on which way to go? Is there a recommended max number of 
haproxy instances per node/core?

Thanks.
-Simon

Re: single or many haproxy instances

[Buckholz, Zachary]

My understanding, and I could very well be wrong. Is that HAProxy is not
SMP aware, it's single threaded and will not automatically take advantage
of systems with multiple CPU's or cores. Other than the OS scheduler moving
things around.

Running multiple instances allows you to peg each  instance to a particular
CPU, core.

Is this correct?


On Tue, Jul 1, 2014 at 12:54 PM, Justin Franks justin.fra...@lithium.com
wrote:

  Not sure why you would run multiple HAProxy in one node. I don't
 understand what you want to do. But...

 Look into using Consul to help load balance/cluster your HAProxy
 instances. That is what we are doing. Simple and works great. Think of
 Consul as a Global load balancing service that works internally.

 Consul will look at all your instances (HAProxy or whatever) and
 round-robin or weight load balance to all of them based on health checks
 you plug in. I don't know if this would solve your prob though.



 *
 Justin Franks
 Lead Operations Engineer
 SaaS, Cloud, Data Centers  Infrastructure
 Lithium Technologies, Inc
 225 Bush St., 15th Floor
 San Francisco, CA 94104
 tel: +1 415 757 3100 x3219
   --
 *From:* Xu (Simon) Chen xche...@gmail.com
 *Sent:* Monday, June 30, 2014 7:38 AM
 *To:* HAProxy
 *Subject:* single or many haproxy instances

Hi folks,

 I am writing a simple load balancer as a service to automate haproxy
 configuration while providing a simple API to users, who only need to give
 a few simple specifications of the load balancer they want.

  I am trying to decide whether to run multiple haproxy instances or a
 single instance on a particular node. I currently use jinja2 template to
 combine all services into a single haproxy configuration file and run a
 single instance of haproxy. Every time, when a service spec is changed, I
 run check config mode, and only reload the config if the test passes. But I
 fear that a single incorrect service spec would prevent everyone else from
 updating their services, unless I maintain some last-known good config for
 every service.

  Managing one haproxy instance for every service solves this problem, but
 I might end up with too many processes on a single box.

  Any recommendations on which way to go? Is there a recommended max number
 of haproxy instances per node/core?

 Thanks.
  -Simon




-- 
*Zachary Buckholz*
E: zachary.buckh...@pearson.com
T: 480-457-7789

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