Thanks Michael. My answers are below in line. Joaquín ___________________________________________________________________ Gerente de Desarrollo, eHealth Systems <http://www.ehs.cl/> Research Fellow, Escuela de Medicina de Harvard <http://hms.harvard.edu/> Moderador, GHDOnline.org <http://www.ghdonline.org/>
On Wed, Apr 25, 2012 at 11:52 AM, Michael Downey <[email protected]>wrote: > Hi Joaquin, > > On Tue, Apr 24, 2012 at 3:45 PM, Joaquín Blaya > <[email protected]> wrote: > > We want to run multiple instances of OpenMRS, one instance per > organization > > using it, and we're hoping to have hundreds of organizations. > > Would you be installing your databases on the same tier (same VM's) as > the app server? If so, and you went with multiple instances of Tomcat > per VM, would you be using multiple running instances of MySQL or > multiple schemas within the same database instance? > Good question, I hadn't decided on that. My initial guess would be multiple schemas on the same database instance, but I'd be happy to hear feedback on the other option. > > Personally I don't like running multiple production applications on a > single VM, especially when they're mission-critical, because it limits > how quickly you can respond to change. Although retail providers of > VM's don't often have a cost model that reflects it, the additional > hardware utilization by having multiple small VM's vs. fewer large > VM's is negligible in light of the scalability and redundancy benefits > it offers, IMHO. > Yep, agreed. I see in Rackspace for example that having 2 2Gb machines or 1 4Gb machine is the same cost. Unfortunately, that's not the same here in Chile (so we'll have to evaluate if we go with servers in the US). But the question is in 2 2GB machines you'll be able to run 2 instances of OpenMRS, while with 1 4Gb machine you could potentially run 3 OpenMRS instances (50% more), and that commercially could be important. Could you tell me or point me to a page which describes the disadvantages or risks of multiple tomcat instances for example what you mean by limiting how quickly you can respond to change, or how or if the tomcat instances could interact with each other. > Either way you would have some disk space and memory constraints for > the database that you forgot to mention (at least in this thread). > > yes, for disk space, it's not a problem, What we find is that we can have 100 - 200 Gb of hard drive for an 8 Gb machine for example, so it would mean ~7 Gb of space per OpenMRS, and our instances our going to have tens of thousands of patients, and not more. For memory constraints, I don't know exactly what you mean. I think the RAM used and the cost of each VM are the key cost factors that I'm trying to balance. Thanks, Joaquin > Best regards, > Michael Downey > OpenMRS Community Infrastructure Team > [email protected] - http://openmrs.org/ > _________________________________________ To unsubscribe from OpenMRS Implementers' mailing list, send an e-mail to [email protected] with "SIGNOFF openmrs-implement-l" in the body (not the subject) of your e-mail. [mailto:[email protected]?body=SIGNOFF%20openmrs-implement-l]
