On Thu, Mar 08, 2018 at 05:03:10PM -0600, Eric Blake wrote: > Recent patches clarified documentation to point out that within > the life of a single connection, the .can_FOO helpers should > return consistent results, and that callers may cache those > results. But at least in the case of .can_fua, we aren't really > caching things; depending on the overhead involved, calling out > to the plugin's .can_fua on every .pwrite with FUA requested > may be noticeable overhead compared to caching it. Any cache > must not be a static variable, as it can differ between > connections. > > Signed-off-by: Eric Blake <[email protected]> > --- > TODO | 4 ++++ > 1 file changed, 4 insertions(+) > > diff --git a/TODO b/TODO > index b6fb0b1..1e0f483 100644 > --- a/TODO > +++ b/TODO > @@ -40,6 +40,10 @@ General ideas for improvements > ones like offset) can fail to initialize if they can't guarantee > strict alignment and don't want to deal with bounce buffers. > > +* Add per-connection caching of .can_FOO callbacks (we already have > + some: .can_write is only called once, but .can_fua is called on > + every request with the FUA flag set). > + > Suggestions for plugins > ----------------------- >
ACK series up to and including this patch. I've got some comments on the final (RFC) patch. Rich. -- Richard Jones, Virtualization Group, Red Hat http://people.redhat.com/~rjones Read my programming and virtualization blog: http://rwmj.wordpress.com libguestfs lets you edit virtual machines. Supports shell scripting, bindings from many languages. http://libguestfs.org _______________________________________________ Libguestfs mailing list [email protected] https://www.redhat.com/mailman/listinfo/libguestfs
