Comment 11 for bug 1396787

With 1.1ubuntu1.18.04.3 u-u runs in ~3s when no package should be updated but there are upgradable packages in -updates.

https://objectstorage.prodstack4-5.canonical.com/v1/AUTH_77e2ada1e7a84929a74ba3b87153c0ac/autopkgtest-bionic/bionic/amd64/u/unattended-upgrades/20180713_084216_9f8ee@/log.gz :
...
Initial blacklisted packages:
Initial whitelisted packages:
Starting unattended upgrades script
Allowed origins are: o=Ubuntu,a=bionic, o=Ubuntu,a=bionic-security, o=UbuntuESM,a=bionic
No packages found that can be upgraded unattended and no pending auto-removals
2.71user 0.12system 0:02.84elapsed 99%CPU (0avgtext+0avgdata 78924maxresident)k
0inputs+7736outputs (0major+22416minor)pagefaults 0swaps
...

The test for 1.1ubuntu1.18.04.4 was most likely run on a slower system where the same run takes ~5s.

https://objectstorage.prodstack4-5.canonical.com/v1/AUTH_77e2ada1e7a84929a74ba3b87153c0ac/autopkgtest-bionic/bionic/amd64/u/unattended-upgrades/20180713_124827_de117@/log.gz :
...
Initial blacklisted packages:
Initial whitelisted packages:
Starting unattended upgrades script
Allowed origins are: o=Ubuntu,a=bionic, o=Ubuntu,a=bionic-security, o=UbuntuESM,a=bionic
No packages found that can be upgraded unattended and no pending auto-removals
5.01user 0.14system 0:05.16elapsed 99%CPU (0avgtext+0avgdata 78992maxresident)k
0inputs+7736outputs (0major+22427minor)pagefaults 0swaps
...