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
On Mon, Nov 09, 2020 at 07:26:13PM -0500, Robert Buck wrote:> 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?The man pages you're pointing to here are obsolete. All accurate information is now in the wiki.> - *aio ** -> > https://www.samba.org/samba/docs/current/man-html/smb.conf.5.html#AIOREADSIZEObsolete. All reads/writes should now be done via the pthreadpool. Or via io_uring.> - *write cache* -> > https://www.samba.org/samba/docs/current/man-html/smb.conf.5.html#WRITECACHESIZEObsolete and code now removed.> - *vfs_cacheprime * > https://www.samba.org/samba/docs/current/man-html/vfs_cacheprime.8.htmlObsolete. Let the kernel do its thing.> - *vfs_full_audit* > https://www.samba.org/samba/docs/current/man-html/vfs_full_audit.8.htmlAll audit code will slow things down :-).> 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).The meta-data being fetched on directory read is seems like what is causing problems. Funding Samba to add directory leasing code will probably help greatly here.
Awesome, thanks! On Mon, Nov 9, 2020 at 8:06 PM Jeremy Allison <jra at samba.org> wrote:> On Mon, Nov 09, 2020 at 07:26:13PM -0500, Robert Buck wrote: > > 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? > > The man pages you're pointing to here are obsolete. All > accurate information is now in the wiki. > > > - *aio ** -> > > > https://www.samba.org/samba/docs/current/man-html/smb.conf.5.html#AIOREADSIZE > > Obsolete. All reads/writes should now be done via the pthreadpool. Or > via io_uring. > > > - *write cache* -> > > > https://www.samba.org/samba/docs/current/man-html/smb.conf.5.html#WRITECACHESIZE > > Obsolete and code now removed. > > > - *vfs_cacheprime * > > > https://www.samba.org/samba/docs/current/man-html/vfs_cacheprime.8.html > > Obsolete. Let the kernel do its thing. > > > - *vfs_full_audit* > > > https://www.samba.org/samba/docs/current/man-html/vfs_full_audit.8.html > > All audit code will slow things down :-). > > > 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). > > The meta-data being fetched on directory read is seems like what > is causing problems. Funding Samba to add directory leasing code > will probably help greatly here. > >-- 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