On Fri, 26 Feb 2016, Eric Wheeler wrote: > On Fri, 26 Feb 2016, Marc MERLIN wrote: > > > On Fri, Feb 26, 2016 at 04:55:02AM +0000, Eric Wheeler wrote: > > > According to Documentation/bcache.txt: > > > "" If you're booting up and your cache device is gone and never > > > coming back, you can force run the backing device: > > > echo 1 > /sys/block/sdb/bcache/running > > > [...] > > > The backing device will still use that cache set if it shows up > > > in the future, but all the cached data will be invalidated. "" > > > > > > So it seems that you are safe. (It would be interesting to know how it > > > invalidates the cache. Maybe bumps the Set UUID? Not sure.) > > > > Yeah, that was my understanding too, but I wanted to make sure. > > Strangely (worringly so?) the cache was replayed at boot, and this time > > nothing crashed, or any traceback. > > Now I'm wondering if it pushed garbage onto my filesystem :-/ > > I'm not convinced that journal replay will writeback, especially because > of the documentation stating that forcing a bdev into a running state > invalidates its cache. I think it just keeps the datastructures in good > shape on the cachedev, even though the cachedev was invalidated by forcing > a 'running' state. Hi Marc, Thank you for your help investigating. The two patches resulting from our testing are on their way into 4.5. How has it been running since? Any new backtraces to investigate? -Eric > > > Marc > > -- > > "A mouse is a device used to point at the xterm you want to type in" - A.S.R. > > Microsoft is to operating systems .... > > .... what McDonalds is to gourmet cooking > > Home page: http://marc.merlins.org/ | PGP 1024R/763BE901 > > > -- > To unsubscribe from this list: send the line "unsubscribe linux-bcache" in > the body of a message to majordomo@xxxxxxxxxxxxxxx > More majordomo info at http://vger.kernel.org/majordomo-info.html > -- To unsubscribe from this list: send the line "unsubscribe linux-bcache" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
