Re: Varnish and Perlbal
André Cruz [EMAIL PROTECTED] writes: Right now I have 2 Perlbals balancing requests to 4 apache backends. I'm very happy with Perlbal's load balancing capabilities so I'm looking for the best way to integrate varnish with this Perlbal + Apache configuration. Which should come first in the flow; Perbal or Varnish? Probably the easiest way to integrate Varnish, at least to begin with, is to run it on the same servers as Apache. This way, cache misses are processed without network overhead, and you can easily run Varnish on just one server in each pair to compare performance. Running Varnish on the Perlbal servers will halve the load on each Apache server, but increase the response time for cache misses. DES -- Dag-Erling Smørgrav Senior Software Developer Linpro AS - www.linpro.no ___ varnish-misc mailing list varnish-misc@projects.linpro.no http://projects.linpro.no/mailman/listinfo/varnish-misc
Re: Varnish and Perlbal
Ok, I'll try it both ways to test. And regarding my other question... Should Perlbal handle the request first, and pass it to some varnish process or should varnish process the request first and send only the misses to PerlBal+Apache? Perlbal is probably better at load-balancing since it is it's core function, no? Thanks for your help, André On 2007/07/02, at 12:43, Dag-Erling Smørgrav wrote: André Cruz [EMAIL PROTECTED] writes: Right now I have 2 Perlbals balancing requests to 4 apache backends. I'm very happy with Perlbal's load balancing capabilities so I'm looking for the best way to integrate varnish with this Perlbal + Apache configuration. Which should come first in the flow; Perbal or Varnish? Probably the easiest way to integrate Varnish, at least to begin with, is to run it on the same servers as Apache. This way, cache misses are processed without network overhead, and you can easily run Varnish on just one server in each pair to compare performance. Running Varnish on the Perlbal servers will halve the load on each Apache server, but increase the response time for cache misses. DES -- Dag-Erling Smørgrav Senior Software Developer Linpro AS - www.linpro.no ___ varnish-misc mailing list varnish-misc@projects.linpro.no http://projects.linpro.no/mailman/listinfo/varnish-misc
Re: Varnish and Perlbal
André Cruz [EMAIL PROTECTED] writes: And regarding my other question... Should Perlbal handle the request first, and pass it to some varnish process or should varnish process the request first and send only the misses to PerlBal+Apache? Isn't that really the same question? Either you run Varnish in front of Perlbal on the Perlbal servers, or you run it in front of Apache on the Apache servers. Perlbal is probably better at load-balancing since it is it's core function, no? Considering that Varnish doesn't do load balancing at all (yet), I would concur that Perlbal is probably better at it :) DES -- Dag-Erling Smørgrav Senior Software Developer Linpro AS - www.linpro.no ___ varnish-misc mailing list varnish-misc@projects.linpro.no http://projects.linpro.no/mailman/listinfo/varnish-misc
Re: Varnish and Perlbal
- André Cruz [EMAIL PROTECTED] wrote: Ok, I'll try it both ways to test. And regarding my other question... Should Perlbal handle the request first, and pass it to some varnish process or should varnish process the request first and send only the misses to PerlBal+Apache? Perlbal is probably better at load-balancing since it is it's core function, no? Thanks for your help, André André, If we can assume one of the reasons you want to use Perlbal is to achieve some sort of failover capability, I would say place Perlbal in front of Varnish. If you have another provision to handle that and you only want to improve performance I would say it depends on your application really. I completely agree with DES though that implementing Varnish locally on the same box as apache is indeed the path of least configuration and fewest changes :P From what I have read on Perlbal it should be suited for placement in front of a cache such as varnish. Could I ask what your experience with Perlbal is? Is it a nice loadbalancer? How does your setup with it look like? What kind of traffice do you see? I gather the Varnish project is looking to implement some sort of basic load balancing capabilities into Varnish at some point in time. Regards -- Denis Braekhus - Teknisk Ansvarlig ABC Startsiden AS http://www.startsiden.no ___ varnish-misc mailing list varnish-misc@projects.linpro.no http://projects.linpro.no/mailman/listinfo/varnish-misc
Re: Varnish and Perlbal
On 2007/07/02, at 14:59, Dag-Erling Smørgrav wrote: André Cruz [EMAIL PROTECTED] writes: And regarding my other question... Should Perlbal handle the request first, and pass it to some varnish process or should varnish process the request first and send only the misses to PerlBal+Apache? Isn't that really the same question? Either you run Varnish in front of Perlbal on the Perlbal servers, or you run it in front of Apache on the Apache servers. Well... You can run varnish on the Perlbal servers and Perbal can still be in front of Varnish. But since varnish doesn't do load balancing it seems that it's better to let Perlbal handle the request first. I would prefer to run Varnish on the Perlbal machines because they have 4 processors and lots of RAM, largely unused by perlbal. The apache machines on the other hand :) Again, if Varnish can't select a backend from a pool to satisfy cache misses then I may just as well have one Varnish for each apache and run them on the same machine... We'll see. Perlbal is probably better at load-balancing since it is it's core function, no? Considering that Varnish doesn't do load balancing at all (yet), I would concur that Perlbal is probably better at it :) Ok, got it. :) Thanks again, André ___ varnish-misc mailing list varnish-misc@projects.linpro.no http://projects.linpro.no/mailman/listinfo/varnish-misc
Re: Varnish and Perlbal
On 2007/07/02, at 15:00, Denis Brækhus wrote: André, If we can assume one of the reasons you want to use Perlbal is to achieve some sort of failover capability, I would say place Perlbal in front of Varnish. If you have another provision to handle that and you only want to improve performance I would say it depends on your application really. I completely agree with DES though that implementing Varnish locally on the same box as apache is indeed the path of least configuration and fewest changes :P I'll start with that scenario then. From what I have read on Perlbal it should be suited for placement in front of a cache such as varnish. Could I ask what your experience with Perlbal is? Is it a nice loadbalancer? How does your setup with it look like? What kind of traffice do you see? I use Perlbal for more than a year now and it has been a very good experience. Besides the great performance we have developed some custom plugins for it which I don't think would be possible with other solutions. We have numerous applications that use it... As an example, in one of them we have 2 perlbal servers in front of a pool of 4 apache servers and a traffic of about 40 Mbit/s. Without Perlbal all the apache workers would get used up quickly. Hope it helps, André Cruz ___ varnish-misc mailing list varnish-misc@projects.linpro.no http://projects.linpro.no/mailman/listinfo/varnish-misc
