Re: [Libguestfs] [libnbd PATCH] python: Allow control over copy/share of nbd.Buffer

On Tue, Jun 14, 2022 at 07:58:08AM -0500, Eric Blake wrote: > Add new methods nbd.Buffer.{to,from}_buffer that avoid the copying > present in the existing nbd.Buffer.{to,from}_bytearray. The reduction > in copies possible by this approach is no longer quite as necessary, > now that aio_p{read,write} have been converted to take buffers > directly. However, there is still one (marginal) benefit: if you use > h.set_pread_initialize(False), and create a new buffer for every I/O > (rather than reusing a buffer pool), nbd.Buffer(n) handed to > h.aio_pread then buf.to_buffer() is slightly faster than handing a > bytearray(n) directly to h.aio_pread, because we are able to skip the > step of pre-zeroing the buffer. > --- >

Acked-by: Richard W.M. Jones <rjones(a)redhat.com&gt; Rich.