Re: [PATCH 2/2] ksmbd: smbd: change the default maximum read/write, receive size

[Steve French <smfrench@gmail.com>]

I was concerned because I saw significant improvements in large i/o
(file copy to or from the server) to Windows and Azure going to 1MB
(negotiated max read/write size), then slightly better to 2MB and
slightly better still to 4MB (was hard to show gain with 8MB in my
earlier tests though)

On Sun, Jan 9, 2022 at 7:37 PM Hyunchul Lee <hyc.lee@gmail.com> wrote:
>
> 2022년 1월 9일 (일) 오후 9:56, Namjae Jeon <linkinjeon@kernel.org>님이 작성:
> >
> > 2022-01-09 15:44 GMT+09:00, Steve French <smfrench@gmail.com>:
> > > Do you have more detail on what the negotiated readsize/writesize
> > > would be for Windows clients with this size? for Linux clients?
> > Hyunchul, Please answer.
> >
>
> For a Linux client, if connected using smb-direct,
> the size will be 1048512. But connected with multichannel,
> the size will be 4MB instead of 1048512. And this causes
> problems because the read/write size is bigger than 1048512.
> It looks like a bug. I have to limit the ksmbd's SMB2 maximum
> read/write size for a test.
>
> For Windows clients, the actual read/write size is less than
> 1048512.
>
> > >
> > > It looked like it would still be 4MB at first glance (although in
> > > theory some Windows could do 8MB) ... I may have missed something
> > I understood that multiple-buffer descriptor support was required to
> > set a read/write size of 1MB or more. As I know, Hyunchul is currently
> > working on it.
> > It seems to be set to the smaller of max read/write size in smb-direct
> > negotiate and max read/write size in smb2 negotiate.
> >
> > Hyunchul, I have one question more, How did you get 1048512 setting value ?
> > >
>
> I remember when the size was 1MB, Windows clients requested read/write with
> 1048512 and 64.
>
> > > On Sat, Jan 8, 2022 at 8:43 PM Namjae Jeon <linkinjeon@kernel.org> wrote:
> > >>
> > >> 2022-01-07 14:45 GMT+09:00, Hyunchul Lee <hyc.lee@gmail.com>:
> > >> > Due to restriction that cannot handle multiple
> > >> > buffer descriptor structures, decrease the maximum
> > >> > read/write size for Windows clients.
> > >> >
> > >> > And set the maximum fragmented receive size
> > >> > in consideration of the receive queue size.
> > >> >
> > >> > Signed-off-by: Hyunchul Lee <hyc.lee@gmail.com>
> > >> Acked-by: Namjae Jeon <linkinjeon@kernel.org>
> > >
> > >
> > >
> > > --
> > > Thanks,
> > >
> > > Steve
> > >
>
>
>
> --
> Thanks,
> Hyunchul



-- 
Thanks,

Steve