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Of course you _can_ do whatever you like. However, if you insist on going against the explicit recommendations of the test suite developers, in ways that a moments thought tells you is likely to give unreliable results, then don't be surprised if you get anomalous results. --Ian On 12 Jul 2012, at 11:37, Alessandra Forti wrote: >> The latency tests will not significantly disrupt the bandwidth tests, so from that point of view there is no problem, but they will look worse than they > should, in a way that is dependent on exactly how many other tests you run. In particular you may see apparent lost packets suggesting you have a problem > where you do not. > > But then if they really have packet loss they have nothing to measure it with. I think it is better to setup these tests and look at what happens and how much the effect of the bandwidth tests really is than not setting them up at all. > > cheers > alessandra > > On 12/07/2012 11:19, Ian Collier wrote: >> The problem is that the latency tests will be tainted by the bandwidth tests, and end up telling not very much that is useful. >> >> Even though the individual bandwidth tests run only for a limited time, they add up once you are testing against a community. (And we already increased the time for each of our bandwidth tests to 40 seconds because otherwise they do not have time to ramp up properly.) >> >> The latency tests will not significantly disrupt the bandwidth tests, so from that point of view there is no problem, but they will look worse than they should, in a way that is dependent on exactly how many other tests you run. In particular you may see apparent lost packets suggesting you have a problem where you do not. >> >> --Ian >> >> On 12 Jul 2012, at 11:11, Elena Korolkova wrote: >> >>> Hi Ian and Ewan >>> >>> actually it was my understanding at the beginning and I configured the machine for bandwidth tests only. >>> It would be nice if we have kind of "official" point of view: what we need to install for sites with one machines. >>> Adding latency tests as Alessandra suggesting is not a big deal. >>> >>> Many thanks to you and Alessandra. >>> >>> Elena >>> >>> On 12 Jul 2012, at 10:43, Ewan MacMahon wrote: >>> >>>>> -----Original Message----- >>>>> From: Testbed Support for GridPP member institutes [mailto:TB- >>>>> [log in to unmask]] On Behalf Of Ian Collier >>>>> Sent: 12 July 2012 10:37 >>>>> >>>>> You don't want bandwidth and latency tests running on/against the same >>>>> machine. (The bandwidth tests running are likely to make the latency >>>>> results meaningless.) >>>>> >>>> Indeed, I thought the plan was for the original six sites with >>>> a pair of boxes to run both, and the sites with just the one >>>> new machine (that was going to be a gridmon node) would now be >>>> set up as a PerfSonar bandwidth box, and those sites just wouldn't >>>> have latency measurements. >>>> >>>> In other words, I think Elena's current configuration is what I'd >>>> expect it to be. >>>> >>>> Ewan >>> __________________________________________________ >>> Dr Elena Korolkova >>> Email: [log in to unmask] >>> Tel.: +44 (0)114 2223553 >>> Fax: +44 (0)114 2223555 >>> Department of Physics and Astronomy >>> University of Sheffield >>> Sheffield, S3 7RH, United Kingdom > > > -- > Facts aren't facts if they come from the wrong people. (Paul Krugman) >