We have a big drive that we've split up using LVM. We allocated one segment to the root filesystem and several other segments to other filesystems. Then we wanted to add more space to the root filesystem, so we carved out another segment at the unallocated end and added it (meaning that the root filesystem is composed of two disjoint segments).
Lately we've been having some I/O performance issues and the thought is that the non-contiguous root volume could be to blame. We're considering moving things around to make the root volume one (contiguous) segment, in hopes of improving performance (the thought being that this will make it easier to access things).
Another school of thought is that LVM has this all sorted out and it's not going to make any difference (other than to make the graphic of the drive layout a bit more compact).
What's the likely penalty we're paying for the two-segment volume?