Just to finish off this subject. It was (kind of) a bug in the test suite: The test suite assumed that fstrim would trim the journal as well as the file content. I adjusted the test so it only measures the trimming of the file content, not any other metadata on the disk, and now the test works reliably. Rich. -- Richard Jones, Virtualization Group, Red Hat http://people.redhat.com/~rjones Read my programming and virtualization blog: http://rwmj.wordpress.com libguestfs lets you edit virtual machines. Supports shell scripting, bindings from many languages. http://libguestfs.org -- To unsubscribe from this list: send the line "unsubscribe linux-fsdevel" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html