Hi Raymond, At those concurrency levels I would suspect network tuning may help. Does dmesg show anything interesting on the load balancers during your testing? For high levels of concurrency on a NAT'd firewall or load balancer I specifically remember having to adjust ip_conntrack_max upwards. Perhaps network buffers as well. -Jeff > -----Original Message----- > From: linux-cluster-bounces@xxxxxxxxxx [mailto:linux-cluster-bounces@xxxxxxxxxx] > On Behalf Of Raymond Setchfield > Sent: Tuesday, July 07, 2009 8:35 AM > To: linux-cluster@xxxxxxxxxx > Subject: Trying to locate the bottleneck > > Hi > > I am trying to find a problem here with a setup which I am currently > testing. > > This is the current setup which I have at the moment > > 15 web farm servers which are running vhost-ldap module and also have > ldap caching enabled. Which are behind 2 Load balancer servers which are > in fail over. The software which it is currently running is Piranha on > the load balancers. > > I am using siege to get some benchmarking done on these to test > basically their availability when pushing high concurrency. > > At 100 (99.60 according to siege) Concurrent Connection it appears to be > all ok with 99.89%. At 120 (119.52 according to siege) Concurrent > connections I get 99.9%, and at 130 (129.51 according to siege) > Concurrent Connections I get 100% availability. > > However pushing it any further than this, for example 150 concurrent > connections it is falling over and siege bails out with multiple > connection time outs. I am trying to find the bottle neck here and I am > wondering if it is software which I am using for the load balancers or a > limitation with apache. > > The command I am using for siege is pretty simple nothing special; > > siege --concurrent=150 --internet --file=urls.txt --benchmark --time=60M > > My lvs.cf file can be found here to show you guys the config which I am > using. > > http://pastebin.com/m52d6cc23 > > Any help would be greatly appreciated > > Many Thanks > > R. > > -- > Linux-cluster mailing list > Linux-cluster@xxxxxxxxxx > https://www.redhat.com/mailman/listinfo/linux-cluster -- Linux-cluster mailing list Linux-cluster@xxxxxxxxxx https://www.redhat.com/mailman/listinfo/linux-cluster
