autobuild[sn-devel-184]: intermittent test failure detected

[autobuild]

The autobuild test system (on sn-devel-184) has detected an intermittent failing test in 
the current master tree.

The autobuild log of the failure is available here:

   https://git.samba.org/autobuild.flakey.sn-devel-184/2019-04-04-1601/flakey.log

The failure seems to be in the "samba-none-env" suite, whose build logs are available here:

   https://git.samba.org/autobuild.flakey.sn-devel-184/2019-04-04-1601/samba-none-env.stderr
   https://git.samba.org/autobuild.flakey.sn-devel-184/2019-04-04-1601/samba-none-env.stdout
  
The top commit at the time of the failure was:

commit 00874b614449b094300a4e249ead22618031b1d8
Author: Gary Lockyer <gary at catalyst.net.nz>
Date:   Mon Apr 1 16:49:38 2019 +1300

    python join: Set index transaction cache size.
    
    The default value is too small for joining a large domain.  So we specify a
    size of 200,000 which is suitable for domains with up to 100,000 users.
    
    At a later date this could be added as a parameter to the join, but
    200,000 should be suitable for now.
    
    Signed-off-by: Gary Lockyer <gary at catalyst.net.nz>
    Reviewed-by: Andrew Bartlett <abartlet at samba.org>
    
    Autobuild-User(master): Andrew Bartlett <abartlet at samba.org>
    Autobuild-Date(master): Thu Apr  4 07:45:03 UTC 2019 on sn-devel-144

and the last 50 lines of the stdout log were:

[193(3283)/228 at 30m58s] pidl.tdr
[194(3289)/228 at 30m58s] pidl.test_util
[195(3295)/228 at 30m58s] pidl.typelist
[196(3351)/228 at 30m58s] pidl.util
[197(3423)/228 at 30m58s] pidl.wireshark-conf
[198(3472)/228 at 30m58s] pidl.wireshark-ndr
[199(3512)/228 at 30m59s] tdb.python
[200(3566)/228 at 30m59s] samba.tests.dsdb_lock
[201(3573)/228 at 32m13s] samba.tests.samba_tool.visualize
[202(3584)/228 at 32m16s] samba.tests.samba_tool.provision_password_check
[203(3588)/228 at 32m25s] samba.tests.samba_tool.help
[204(3589)/228 at 33m32s] samba.tests.domain_backup_offline
[205(3593)/228 at 35m2s] samba.tests.lsa_string
[206(3597)/228 at 35m2s] samba.tests.loadparm
[207(3600)/228 at 35m2s] samba4.blackbox.samba3dump
[208(3601)/228 at 35m3s] samba4.blackbox.upgrade
[209(3609)/228 at 35m31s] samba4.blackbox.provision.py
[210(3616)/228 at 36m22s] samba4.blackbox.supported_features
[211(3622)/228 at 36m32s] samba4.blackbox.start_backup
[212(3625)/228 at 36m40s] samba4.blackbox.upgradeprovision.current
[213(3632)/228 at 37m48s] samba4.blackbox.setpassword.py
[214(3638)/228 at 38m1s] samba4.blackbox.newuser.py
[215(3649)/228 at 38m18s] samba4.blackbox.group.py
[216(3678)/228 at 38m46s] samba4.blackbox.provision-backend
[217(3682)/228 at 38m56s] samba4.blackbox.renamedc.sh
[218(3693)/228 at 39m26s] samba4.dsdb.samdb.ldb_modules.unique_object_sids
[219(3699)/228 at 39m26s] samba4.dsdb.samdb.ldb_modules.encrypted_secrets.tdb
[220(3714)/228 at 39m26s] samba4.dsdb.samdb.ldb_modules.encrypted_secrets.mdb
[221(3729)/228 at 39m26s] lib.audit_logging.audit_logging
UNEXPECTED(failure): lib.audit_logging.audit_logging.test_audit_get_timestamp(none)
REASON: Exception: Exception: difftime(after, actual) >= 0
../../lib/audit_logging/tests/audit_logging_test.c:827: error: Failure!

FAILED (1 failures, 0 errors and 0 unexpected successes in 0 testsuites)

A summary with detailed information can be found in:
  ./bin/ab/summary
TOP 10 slowest tests
samba.tests.docs -> 430
samba4.blackbox.upgradeprovision.alpha13 -> 158
samba4.blackbox.upgradeprovision.release-4-0-0 -> 153
samba4.blackbox.schemaupgrade -> 115
samba4.blackbox.dbcheck.release-4-0-0 -> 102
samba4.blackbox.dbcheck.release-4-1-0rc3.quick -> 99
samba4.blackbox.dbcheck.release-4-0-0.quick -> 98
samba4.blackbox.dbcheck.release-4-1-0rc3 -> 96
samba.tests.domain_backup_offline -> 90
samba4.blackbox.dbcheck.alpha13.quick -> 76
ERROR: test failed with exit code 1
Makefile:16: recipe for target 'test' failed