On Thu, Sep 27, 2007 at 03:31:23PM +0200, Ingo Molnar wrote: > > * Jarek Poplawski <[EMAIL PROTECTED]> wrote: ... > > OK, but let's forget about fixing iperf. Probably I got this wrong, > > but I've thought this "bad" iperf patch was tested on a few nixes and > > linux was the most different one. The main point is: even if there is > > no standard here, it should be a common interest to try to not differ > > too much at least. So, it's not about exactness, but 50% (63 -> 95) > > change in linux own 'definition' after upgrading seems to be a lot. > > So, IMHO, maybe some 'compatibility' test could be prepared to compare > > a few different ideas on this yield and some average value could be a > > kind of at least linux' own standard, which should be emulated within > > some limits by next kernels? > > you repeat your point of "emulating yield", and i can only repeat my > point that you should please read this: > > http://lkml.org/lkml/2007/9/19/357 > > because, once you read that, i think you'll agree with me that what you > say is simply not possible in a sane way at this stage. We went through > a number of yield implementations already and each will change behavior > for _some_ category of apps. So right now we offer two implementations, > and the default was chosen empirically to minimize the amount of > complaints. (but it's not possible to eliminate them altogether, for the > reasons outlined above - hence the switch.)
Sorry, but I think you got me wrong: I didn't mean emulation of any implementation, but probably the some thing you write above: emulation of time/performance. In my opinion this should be done experimentally too, but with something more objective and constant than current "complaints counter". And the first thing could be a try to set some kind of linux internal "standard of yeld" for the future by averaging a few most popular systems in a test doing things like this iperf or preferably more. Jarek P. - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
