On 22.03.2013 13:34, Heiko Wundram wrote: > Hey! > > I've checked out multiple trunks over the last two weeks of the > current bcache repository (all 3.8.0+), and they all exhibit the > same kind of broken behaviour: after some time (generally around 6 > hours), I/O to the bcache device stops working (I have layered LVM > on top of it, and those devices also stop working, naturally), and > the SSD that's part of the cache set spins continuously at around > 50MB/s I/O on write. It is irrelevant whether I enable discard or > not. I've only tested this with writeback mode.
Hi Heiko, that sounds pretty much the same as what I experienced this week. After finishing some write benchmarks on a bcache device, dirty data blocks have to be synchronized to backing devices really slowly. (20~30 MB/s in my case) That sync job usually takes more than 5 minutes, which makes end users unable to do anything. My test environment: kernel 3.4.23 with bcache patches backported from master. Backing device is configured as MD-RAID10 on spindle drives. Cache mode is writeback. I've also tested with bcache-3.2, but it was not much different from 3.4+. Regards, Dongsu > > Is this a known problem? > > -- > --- Heiko. > -- > To unsubscribe from this list: send the line "unsubscribe linux-bcache" in > the body of a message to [email protected] > 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 [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
