Hi Brian, On Thu, Jan 27, 2011 at 5:37 PM, Brian Bockelman <[log in to unmask]> wrote: > So, if we use TTreeCache on any tree on the file, read-ahead is turned off? To be precise, async reads from ROOT force the cache synchronization with xroot and this may overwrite cache settings of the underlying xroot client (including the readahead size). > I would say this is simply wrong Well, I agree. I will have a closer look and try to fix it. Lukasz