eMing, Christoph, Jens! Ming, 5 years ago or so you added support for dio/aio for the loopback block device, i.e. LO_FLAGS_DIRECT_IO. As I understood it's supposed to improve performance of loopback block devices substantially. I noticed that there's various software that enables it by default (Android, Docker), but a lot of other candidates currently do not (util-linux, Ubuntu Snaps, various systemd tools). We recently got a request to enable it by default in systemd, but information is scarce on the precise effect of enabling this, and whether there are any drawbacks. So my question really is just: is this a flag we should all just enable by default? Is there any reason not to enable it? Should util-linux' losetup defaults be changed regarding this? A brief answer like "yes, please, enable by default" would already make me happy. Thank you, Lennart -- Lennart Poettering, Berlin
