I would say this is not just a case of faster, but more aware. Linux does not have the same meta-data knowledge that the native cache has. There is a layering

I would say this is not just a case of faster, but more aware. Linux does not have the same meta-data knowledge that the native cache has. There is a layering problem which makes it hard to add this. For example: after some page splits and fragmentation pages are no longer stored in physical order. How can a logical read ahead work on the Linux level?