Comment 48 for bug 620074

It does strike me as quite odd how large of a factor the size of the transfer seems to be. When I first start evolution (I have very large folders), the system will exhibit poor interactivity for upwards of 5 to 10 minutes. However, when transferring lots of small files (i.e. module_install'ing), the kernel behaves fine. (although modpost also seems to produce poor interactivity)

I think it might help if we had a kernel developer here to list the kernel block/memory manager/scheduler statistics that might indicate where this I/O wait time is going. If sufficient statistics don't exist, it might be worthwhile to instrument the kernel specifically for this bug. It does seem clear that the bug I intended this ticket to describe is invariant on I/O scheduler, so that's one factor that needn't be accounted for.