The arc_buf_hdr_t is an in-core-only data structure, so it has no version impact. It does not matter where you add an extra field.
However, only add a field to this structure if you really need it... increasing the size of this struct will likely have a negative performance impact on the ARC. -Mark Darren J Moffat wrote: > If I add a new field to arc_buf_hdr_t this has a version impact right? > > I think I need to add a field to it for dealing with encryption of the > L2ARC. > > I'm assuming it should be added at the end and any assignment or > reference to it should be guarded with the usual style of version check > ? Is that sufficient ? >
