Thanks P3R, entirely expected results, and completely missing the point.
An 8-disk RAID-5 has 7 writing spindles plus a write penalty.
An 8-disk RAID-10 has 4 writing spindles. Thus we'd expect an 8-disk R10 to have approx the same WRITE speed as a 5-disk R5, plus a little bonus because of the XOR penalty. And that's exactly what P3R's numbers find.
With same number of spindles (expect maybe very low, where XOR penalty is a higher %), R5 is going to be faster than R10 at WRITING because R10 only uses half of its spindles for write throughput.
SInce I don't expect thta the original participants are likely to be in a position to re-rest the same components, I won't ask for a proper survery, as should have been done int he first place.
So I'll quote myself from above instead.
It's quite dishonest to do -only- write tests --or-- only read tests and then claim one or the other is 'faster'. The arrays will always cost different amounts and have different capacities. So pick and declare your working frame first, and state the parameters you're testing. Otherwise you're just a hack. Like the original article.Besides, the whole point is that this thread is positioned to "refute the claim that R10 is faster than R5", which is just as misleading as the original "myth" that "R10 is faster". My only aim here was to point out that it is not as simple as "which is faster, which is slower", but that the context, usage, and characteristics of the arrays all play a role and there is no universal "faster" at all. Write Performance is not everything, and neither is Read Performance, and so it is disingenuous to test only one and then claim "the speed advantage is a myth".