W dniu 25.08.2016 o 02:03, Christopher James Halse Rogers pisze: Hi! > On Thu, Aug 25, 2016 at 7:21 AM, marcin@xxxxxxxx wrote: [...] >> Does it means that cache is unavailable and only tiering will be in >> bcachefs? >> And... How to mount tiered FS? When I pass one device in mount I'm >> getting: >> bcache: bch_open_as_blockdevs() register_cache_set err insufficient >> devices > > Tiering gets you all the advantages of caching, plus you can (with some > effort) have the combined filesystem size be the sum of the SSD + HDD > capacities, rather than the capacity be determined solely by the > capacity of the slow tier (this is not currently the case for bcachefs). I think that cacheing has at least such advantages over tiering: - allow fast read and write to files compressed with slow alghoritm (gzip) - can be optimized for using SSD drives > To mount a tiered FS you can either pass all the relevant devices to > mount, like: > mount -t bcache /dev/sda:/dev/sdb:/dev/sdc /mountpoint > (I haven't tested this recently) or ensure that all the relevant devices > have been registered with bcache, like so: > echo /dev/sda | sudo tee /sys/fs/bcache/register_quiet > echo /dev/sdb | sudo tee /sys/fs/bcache/register_quiet > echo /dev/sdc | sudo tee /sys/fs/bcache/register_quiet > mount -t bcache /dev/sdb /mountpoint > (you can use any member of the set as the device to mount in this case). Thanks for tip, good to know other way to mount. Marcin -- 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
