podman ps --sort created : not always sorting by created

[edsantiago]

About one in five tries, this gives me the wrong (unexpected) result:

$ img=quay.io/libpod/testimage:20200929
$ ./bin/podman run -d --name c1 $img true;./bin/podman run -d --name c2 $img true;./bin/podman ps -a --sort created
faf3c3ebd4c764dad41ecee6ae0aafb077ef0ae9181f03c05235c8445de779fa
a381df699c40d4a46f4a678b2758154af375bcb1aee445526171afbf3d9f6e76
CONTAINER ID  IMAGE                              COMMAND  CREATED       STATUS                             PORTS   NAMES
a381df699c40  quay.io/libpod/testimage:20200929  true     1 second ago  Exited (0) Less than a second ago          c2
faf3c3ebd4c7  quay.io/libpod/testimage:20200929  true     1 second ago  Exited (0) 1 second ago                    c1

I expect to see c1 before c2, always. It's not a timing issue with -d, because c1.Created < c2.Created:

$ ./bin/podman inspect --format '{{.Name}} {{.Created}}' c1 c2
c1 2020-11-19 13:30:14.806452 -0700 MST
c2 2020-11-19 13:30:14.948358079 -0700 MST

It's not a flake in ps, because for any given run of two containers, podman ps -a --sort created will always return the same order, always always, at least for values of "always" less than a ten-minute while loop.

In every instance when I see this, the CID of c2 is lexically < CID(c1); so much so that it seems improbable (many tens of repeated runs). I don't know if this is helpful. The sorting code looks good to my eye:

podman/pkg/domain/entities/container_ps.go

Lines 139 to 141 in a18365c

	func (a PsSortedCreateTime) Less(i, j int) bool {
	return a.SortListContainers[i].Created < a.SortListContainers[j].Created
	}

I don't know where else to look; am hoping that someone can take a quick look at the sorting code and see something obvious.