in LVM1 there was a limit of 65k extends. So size of extent had to been chosen carefully between wasted space on partitions (to big extent) and maximal possible size of logical volume (too small extent). in lvm2 (according to http://docstore.mik.ua/manuals/hp-ux/en/5992-4589/apa.html) the limit is ~16 million extents. so the default size of 4mb gives ~60TB of LV size.

so is there any point in making the extent larger than 4-16mb on a desktop? is there any performance degradation or other costs of having big number of extents?