On Thu, Jan 28, 2016 at 12:41:21PM +0100, Jens-U. Mozdzen wrote: > Hello Neil & *, > > Zitat von NeilBrown <nfbrown@xxxxxxxxxx>: > >[...] > >I'd like to deprecate /proc/mdstat. It is not really easy to extend. > > while I understand that /proc/mdstat's format might be considered "frozen" > as in "do not confuse old scripts by new formats", I'd hate to see > /proc/mdstat go away without a similar replacement: calling "mdadm" (or any > other CLI) to gather that information is unruly expensive when all you have > to do is "watch cat /proc/mdstat" to manually monitor critical operations. That will not happen soon. Deprecating an interface takes years. > >I'd recommend using "mdadm" to get status of an array, or examine file > >in /sys. > > If there's to be a "new mdstat" in /sys, I'd be fine with that. That would > help migration for those "old scripts grep'ing /proc/mdstat" you rightfully > care about. > > I suggest to include a file format version information on line 1 > "/sys/.../mdstat", that way any client parsing such an interface could > verify the file format first, and bail out if it doesn't support the > currently presented format. All the info you can get from /proc/mdstat can be found in /sys/xxx. There isn't a central mdstat file in sysfs entry, each sysfs entry only export single type info. Version info is uncessary, if we need add new info, we'd just add a new sysfs entry. though the /proc/mdstat will not be deprecated soon, it's highly encouraged app switches to /sys. sysfs entry is easy to parse. And as Neil said, /proc/mdstat is hard to extend, so new info will likely only appear in sysfs. Thanks, Shaohua -- To unsubscribe from this list: send the line "unsubscribe linux-raid" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
