Il 13/11/2012 18:09, Orit Wasserman ha scritto: >> > >>> >> b) do scatter/gather of the pages? > I would prefer to postpone changing the protocol and start with using iov > (writev) > for sending the pages (still sending header and than the page). Later we can > move to scatter/gather I'm not sure of how large the performance gain will be. >> > >> > c) Remove compression of non-zero repetitive pages. > +1 > we can look of identify the zero pages without calling is_dup_page which looks > expensive.
Identifying ballooned zero pages is useful, because those cause the clear_page calls in the kernel even in a guest that has been running for a while. But a generic solution doesn't really matter, because is_dup_page and clear_page shouldn't really be in the profile in practice, except in microbenchmarks. Paolo
