> >> I have no much idea. The 4Kn SSD is totally new to me. Last time I saw > >> Eric Wheeler reported 4Kn hard diver didn't work well as backing device, > >> and I don't find an exact reason up to now. I am not able to say 4Kn is > >> not supported or not, before I have such device to test... > > > > We pulled the 4Kn SSD configuration, it wasn't stable back in v4.1. Not > > sure if the problem has been fixed, but I don't think so. > > > > Here is the original thread: > > > > https://www.spinics.net/lists/linux-bcache/msg05971.html > Yes, this is the problem I wanted to say. Kent suggested me to look into > the extent code, but I didn't find anything suspicious. Also I tried to > buy a 4Kn SSD, but it seemed not for consumer market and I could not > find it from Taobao (www.taobao.com). Its easy to simulate with libvirt: <disk type='block' device='disk'> <driver name='qemu' type='raw' cache='none' io='native' discard='unmap'/> <source dev='/dev/data/coly-dev_cache'/> <blockio logical_block_size='4096' physical_block_size='4096'/> <target dev='sdd' bus='scsi'/> <address type='drive' controller='0' bus='0' target='0' unit='3'/> </disk> Note this line: <blockio logical_block_size='4096' physical_block_size='4096'/> -Eric > > -- > > Coly Li >
