Re: qemu modularization of qemu-5.1 vs libvirt domcapabilities cache?

On Thu, Aug 20, 2020 at 11:48 AM Christian Ehrhardt < christian.ehrhardt(a)canonical.com&gt; wrote: Why is the list of files and stat dates needed? Any change done by RPM to add or remove a file from the directory, should cause the mtime for the directory to be updated. It doesn't really matter what the change is - it only matters that the change is detected. The case for needing to check the files *in* the directory, would be a concern about the modules keeping the same name, but being updated in place. I'm doubtful that this ever occurs for real, as it would cause breakage for running programs. Existing running programs would mmap() or similar the binaries into memory, and cannot be updated in place. Instead, the inode remains alive, and a new file is created with the same name, to replace the old file, and once all file descriptors are closed - the inode is deleted. So, unless there is a hierarchical directory structure - I believe checking the modules directory timestamp is near 100% accuracy for whether modules were added, removed, or updated using "safe" deployment practices either by RPM or "make install". I don't think there was a follow up discussion on the idea. I think that is here. :-) -- Mark Mielke <mark.mielke(a)gmail.com&gt;