On Thu, 2015-04-30 at 07:07 -0700, Daniel Phillips wrote: > > On 04/30/2015 06:48 AM, Mike Galbraith wrote: > > On Thu, 2015-04-30 at 05:58 -0700, Daniel Phillips wrote: > >> On Thursday, April 30, 2015 5:07:21 AM PDT, Mike Galbraith wrote: > >>> On Thu, 2015-04-30 at 04:14 -0700, Daniel Phillips wrote: > >>> > >>>> Lovely sounding argument, but it is wrong because Tux3 still beats XFS > >>>> even with seek time factored out of the equation. > >>> > >>> Hm. Do you have big-storage comparison numbers to back that? I'm no > >>> storage guy (waiting for holographic crystal arrays to obsolete all this > >>> crap;), but Dave's big-storage guy words made sense to me. > >> > >> This has nothing to do with big storage. The proposition was that seek > >> time is the reason for Tux3's fsync performance. That claim was easily > >> falsified by removing the seek time. > >> > >> Dave's big storage words are there to draw attention away from the fact > >> that XFS ran the Git tests four times slower than Tux3 and three times > >> slower than Ext4. Whatever the big storage excuse is for that, the fact > >> is, XFS obviously sucks at little storage. > > > > If you allocate spanning the disk from start of life, you're going to > > eat seeks that others don't until later. That seemed rather obvious and > > straight forward. > > It is a logical falacy. It mixes a grain of truth (spreading all over the > disk causes extra seeks) with an obvious falsehood (it is not necessarily > the only possible way to avoid long term fragmentation). Shrug, but seems it is a solution, and more importantly, an implemented solution. What I gleaned up as a layman reader is that xfs has no fragmentation issue, but tux3 still does. It doesn't seem right to slam xfs for a conscious design decision unless tux3 can proudly display its superior solution, which I gathered doesn't yet exist. > > He flat stated that xfs has passable performance on > > single bit of rust, and openly explained why. I see no misdirection, > > only some evidence of bad blood between you two. > > Raising the spectre of theoretical fragmentation issues when we have not > even begun that work is a straw man and intellectually dishonest. You have > to wonder why he does it. It is destructive to our community image and > harmful to progress. Well ok, let's forget bad blood, straw men... and answering my question too I suppose. Not having any sexy IO gizmos in my little desktop box, I don't care deeply which stomps the other flat on beastly boxen. -Mike -- To unsubscribe from this list: send the line "unsubscribe linux-fsdevel" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
