On Monday May 11, greg.freemyer@xxxxxxxxx wrote: > > And since the mdraid layer is not currently planning to track what has > been discarded over time, when a re-shape comes along, it will > effectively un-trim everything and rewrite 100% of the FS. You might not call them "plans" exactly, but I have had thoughts about tracking which part of an raid5 had 'live' data and which were trimmed. I think that is the only way I could support TRIM, unless devices guarantee that all trimmed blocks read a zeros, and that seems unlikely. You are right that the granularity would have to be at least one stripe. And a re-shape would be interesting, wouldn't it! We could probably avoid instantiating every trimmed block, but in general quite a few would get instantiated.. I hadn't thought about that... NeilBrown -- To unsubscribe from this list: send the line "unsubscribe linux-ext4" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
