Andreas Schäfer wrote: >On 23:14 Tue 14 Mar , Hans Reiser wrote: > > >>I generally believe that the per 4k >>approach used throughout the linux kernel is not as CPU efficient as >>sending larger groups of pages through the layers all at once. In other >>words, there is a reason we have bios, and we need to learn the lesson >>from them that they teach us, and abstract it into a general design >>approach. >> >> > >This is a bit OT, but still: I think you're absolutely right there. This 4k >approach causes funny thing even in completely different areas. > >I've recently been playing around with openMosix (transparent process >migration between Linux hosts over the network) and there the write >preformance is totally spoiled (>50% performance loss) just because >copy_from_user is only called for 4k block when writing (and these >requests then suffer from the high network latency). > > Tell the mosix guys we would be willing to cooperate with them regarding their problem.
>If larger blocks would be used, this performance flaw wouldn't exist at >all... Just my 2 cents > >-Andreas > > > >
