Well what I am trying to do is for example the site is www.testingv.com I have at the f5 check to see if the request is coming from a bot, and if it is then said it to a pool that points to a different virtual host on the appache server using a different port, specifically for bot requests.
Otherwise if www.testingv.com is a normal browser request then send to the main virtual host on port 80 I am trying to see if there is a way with using a single instance 1) Varnish using VCL to recognize that it is a bot 2) If it is a bot request, varnish will then use a different backend. Thanks On Thu, May 5, 2011 at 12:22 PM, Stefan Pommerening <[email protected]> wrote: > Am 05.05.2011 16:26, schrieb Mike Franon: > > Has anyone run multiple instances of varnish on the same server and > how is the performance overall? > > I am looking into it, because I want to serve up the same url, but > depending if it is a bot go to a different backend. > > I am trying to figure out the best way to do that. > > Hi Mike, > although I am not completely understanding your motivation I still can state > that my current customer had two varnish instances running on several > machines. > Therefore it works :) > > The reason was not to run out of file descriptors (I was told...) > Meanwhile I migrated every two instances to a single instance per machine. > > Well, performance (with two instances) was ok when you have cpu in mind. > On the other hand it's not very effective to have the same objects in two > different caches > because virtual memory (and/or file cache of course) isn't shared between > both instances. > This results in a lower hitrate and the double number of backend requests. > > Technically you have to setup two instances using different instance names > using the -n parameter and of course different ports to listen on (client > req and cli). > > A reasonable setup would be to split domain names at the load balancer and > feed > them to different varnish instances - those could be run on same hardware. > On the other hand you double your overhead memory usage (cache > fragmentation, > spare threads and such). > > I personally see no reason why to run more than one varnish instance on the > same > hardware and I think you can do everything in VCL. > > Stefan > > -- > > Dipl.-Inform. Stefan Pommerening > Informatik-Büro: IT-Dienste & Projekte, Consulting & Coaching > http://www.dmsp.de > _______________________________________________ varnish-misc mailing list [email protected] http://www.varnish-cache.org/lists/mailman/listinfo/varnish-misc
