On 17/12/1 上午10:38, Michael Lyle wrote:

On 11/30/2017 06:30 PM, 彭良彦 wrote:

quoted

If the cache device is not persistent like ramdisk,  all data will be lost after reboot. We have to use make-bcache to fix the inconsistent super block of backing device.

Using a non-persistent writeback cache is guaranteed to lose data.
(Writes will only go to the cache device and not make it to the
persistent volume).

Mike

If we use ramdisk as a writethrough cache to improve the read performance, the backing device is a network disk, the super block state of backing device still has chance to be inconsistent due to disconnected network. Like in above reproduce steps, i didn't use a cache device. :-)