Akira Hayakawa

Great. What kind of tests?

Great! Don't clear the caches because it's _not_ successful shutdown. You need to replay the logs after reboot.

@zhouyuan Yes for all. As for the second question, losing un-flushed data is ok because client of block device should submit barrier request (bio flagged with REQ_FLUSH) to ensure that...

@zhouyuan It's the worst case scenario. Writeboost may flush the log for each 4KB write. But the log size is 8KB (4KB header + 4KB data), not 512KB. I call...

I have no plan for further optimization because writing back data in FIFO manner fits log-structured caching as I explained before. And I am wondering if such too extravagant optimization...

That't too bad. In my opinion, bcache has its codebase too complicated and too huge. Only Kent can grab everything in his software. (dm-cache is in similar status) dm-writeboost on...

You are welcome. > Does dm-writeboost not track the written blocks? What happens if i write block A and than read block A but block A is still in the...

@bash99 It's quite dependent on the IO amount and the distribution. Please give me the detail of your benchmark. By the way, it's not dw-boostwrite but dm-writeboost you must be...

@bash99 Also, please share how you setup your dm-writeboost'd device. It's important to know the max_batched_writeback in particular.

I don't know what kind of optimization enhanceio does but generally saying, this could be happening because dm-writeboost's writeback is restricted to do from the older segment to newer segment....