On 27/08/2012 20:55, Kent Overstreet wrote:
On Mon, Aug 27, 2012 at 12:43 PM, Jonathan Tripathy [off-list ref] wrote:
quoted
On 27/08/2012 20:22, Kent Overstreet wrote:
quoted
echo 1 > /sys/fs/bcache/<uuid>/unregister
echo 1 > /sys/block/bcache0/bcache/stop
Ok, so I managed to recreate everything with a block size of 512 bytes.
However, 2 bad things have happened:
1) In my Linux DomU, my fio randomwrite test have gone from about 28k iops
to about 800 iops. Can this be fixed? changing bs and ba to 512 in the fio
config file didn't hep.
Ouch!
Bet the ssd doesn't like those 512 byte journal writes. I'm going to
have to think about that...
Hi Kent,
Ok, a little good news. I managed to sort out the low IOPS issue. When I formatted bcache0 with a 512 block size, I forgot to set the caching mode back to writeback. Once I did that, the IOPS were nice and high again (circa 26k IOPS). Sorry about the noise regarding that non-issue.
I re-tried the windows setup with writeback enabled for the 512B formatted cache. It kernel paniced as per-usual, however for some reason, it's kernel panicking upon every boot now, whereas when it was formatted with 4k sectors, once the system came back up, it was stable (until I tried another windows setup). The debug trace appears to be the same as the one I posted to the list (kernel BUG at fs/bio.c:420! invalid opcode: 0000 [#1] SMP).
I appreciate your time.
Thanks