On 2020/05/12 10:25, Bart Van Assche wrote: > On 2020-05-11 16:18, Bart Van Assche wrote: >> Anyway, can you give the patch below a try? > > The patch in my previous email handles MQ mode but not bio mode. The > attached patch should handle both. > > Thanks, > > Bart. > Bart, The patch looks good to me. However, I have one concern regarding the performance impact of this. When nullblk is used to benchmark the block IO stack overhead, doing this zeroing unconditionally will likely significantly impact measured performance. So may be this zeroing feature should be driven by a modprobe/configfs option ? Doing so, we can keep it off by default, preserving performance, and turn it on when needed as in Alexander use case. Thoughts ? -- Damien Le Moal Western Digital Research
