[Samba] vfs readahead && windows server 2016/2019?

[Robert Buck]

Hi Jeremy, thank you for your very helpful response. We're looking at a few
more options. Would you have the time to provide some guidance on these,
how helpful they may be?


   - *aio ** ->
   https://www.samba.org/samba/docs/current/man-html/smb.conf.5.html#AIOREADSIZE
   - *write cache* ->
   https://www.samba.org/samba/docs/current/man-html/smb.conf.5.html#WRITECACHESIZE
   - *vfs_cacheprime *
   https://www.samba.org/samba/docs/current/man-html/vfs_cacheprime.8.html
   - *vfs_full_audit*
   https://www.samba.org/samba/docs/current/man-html/vfs_full_audit.8.html

If you were to rank the likelihood of these helping, how would you rank
them? Are they still applicable in modern Windows and RHEL?

Background...

Our top challenge right now is Windows Explorer, specifically when you get
properties on a directory, it takes very long to provide a file count, etc,
comparatively to a share from another Windows Server.

We just moved all CTDB volatile persistent state to NVMe and we have not
tested the impact yet, and this may prove significantly beneficial. So the
Windows Explorer issues may prove to be solved during tomorrow's testing.
And we're also planning on testing turning off locking in the root folder
this week, as we've been told this can help a lot too.

Bear in mind, we are likely to have upwards of 500-800 concurrent users per
share. We're running in AWS, for both Samba servers and Windows Server
(desktop streaming).


On Mon, Nov 9, 2020 at 5:36 PM Jeremy Allison <jra at samba.org> wrote:

> On Mon, Nov 09, 2020 at 04:48:31PM -0500, Robert Buck via samba wrote:
> > Quick question...
> >
> > The docs for vfs readahead mention Windows Vista, but what about modern
> > Windows versions? Windows Server 2016 or Windows Server 2019?
>
> vfs_readahead would need to be updated for our
> modern VFS. It only calls Linux readahead for
> sendfile()/pread(), and modern Samba exclusively
> calls pread_send()/pread_recv() with threads
> on most systems.
>
>

-- 

BOB BUCK
SENIOR PLATFORM SOFTWARE ENGINEER

SKIDMORE, OWINGS & MERRILL
7 WORLD TRADE CENTER
250 GREENWICH STREET
NEW YORK, NY 10007
T  (212) 298-9624
ROBERT.BUCK at SOM.COM