[WIP][PATCH] Safe LDB locking for better replication

[Andrew Bartlett]

On Sat, 2017-06-17 at 08:19 +1200, Andrew Bartlett via samba-technical
wrote:
> 
> I can thankfully advise that 5/8 autobuilds I ran on this my tree
> passed last night, with 2 of those being the messaging crash that there
> is already a fix for.  This is not an unknown pass rate, but is much
> better than we have seen for a while.

Rebased on master, 8/9 builds passed, with this the only failure:

[1971(11951)/2129 at 2h24m40s] samba.nss.test using
winbind(ad_member:local)(ad_member:local)
UNEXPECTED(failure): samba.nss.test using winbind(ad_member:local).run
nsstest(ad_member:local)
REASON: Exception: Exception: ERROR getpwent: NSS_STATUS=-1  1
(nss_errno=0)
ERROR getgrent: NSS_STATUS=-1  1 (nss_errno=0)
ERROR Non existent user gave error -1
ERROR Non existent uid gave error -1
ERROR Non existent group gave error -1
ERROR Non existent gid gave error -1
total_errors=6

While there are other known flapping tests, I think we may finally be
getting past the 'most builds fail due to flapping' dramas.

Andrew Bartlett
-- 
Andrew Bartlett                       http://samba.org/~abartlet/
Authentication Developer, Samba Team  http://samba.org
Samba Developer, Catalyst IT          http://catalyst.net.nz/services/samba