On Sun, 27 Mar 2005, Dave Jones wrote: > Am I the only person who is completely fascinated by the > effort being spent here micro-optimising something thats > almost never in a path that needs optimising ? > I'd be amazed if any of this masturbation showed the tiniest > blip on a real workload, or even on a benchmark other than > one crafted specifically to test kfree in a loop. > > That each occurance of this 'optimisation' also saves a handful > of bytes in generated code is it's only real benefit afaics. > Even then, if a functions cache performance is better off because > we trimmed a few bytes from the tail of a function, I'd be > completely amazed. >
I agree, it's amazing that this is treated like a big issue, it's not, and I never meant for it to be a matter of such debate. The whole thing (viewed from where I'm sitting) started when I noticed a few of those redundant NULL checks while reading code, thought I'd clean them up since they were clearly not needed and submit those patches. When those patches then got merged I thought "ok, so this is something that's actually appreciated, guess I might as well do some more when I come across them or maybe even seek them out and get rid of them once and for all"... So I started doing that and more of the patches got merged which (at least to me) confirmed that it was a worthwhile activity, until at some point voices were raised in objection. At that point I felt I needed to explain the "why" of why I was doing it and try and show that it might actually be a bennefit (and I believe the small test I wrote shows it to be either a bennefit in the usual case or at worst a trivial performance hit in the not-so-common case). What I'm trying to find out now is if there's a general consensus that these patches are worthwile and wanted or if they are unwanted and I'm wasting my time. If the patches are wanted I don't mind doing them, but if they are not wanted I don't want to waste my time (nor anyone elses) on them. So, if I could just get peoples comment on that "wanted vs not-wanted" then I could get on with either producing some patches for people or get on with other things and drop this... Or I guess I could just go on making those patches, submit them and then just leave it in the hands of the individual maintainers (which was more or less how I started out)... -- Jesper Juhl - 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/
