On 29/01/2024 06:18, Christoph Hellwig wrote:
Do you have a git tree with all patches somewhere?
Hi Christoph,
Please let me know if you had a chance to look at this series or what
your plans are.
BTW, about testing, it would be good to know your thoughts on power-fail
testing.
I have done much testing for ensuring that writes are properly issued to
HW with no undesired splitting/merging, etc for normal operation. I have
also tested crashing the kernel only to see if atomic writes get
corrupted. This all looks ok.
About PF testing, I have an NVMe M.2 drive, but it supports just 4K
nawupf. In addition, unfortunately the port on my machine does not allow
me to power it off, so I need to plug out the power cable to test PF :(
We do also support atomic writes on our SCSI storage servers, but it is
not practically possible to PF them.
For actual PF testing, I have been using fio in crc64 verify mode with a
couple of tweaks to support atomic writes.
What I find from limited testing for XFS and bdev atomic writes on that
NVMe card is that indeed 4K writes are PF-safe, but 16K (this is an
arbitrary large block size which I chose) is not. But I think all cards
will be 4K PF safe, even if not declared.
Thanks,
John
