Hello,
really thanks for your answer. I will try to investigate to the 2nd problems, and I will
keep you informed if I find something.
For the first one, I am experimenting cache pool as you pointed me to, I never tried it
because the ceph documentation doesn't really encourage this with rbd.
For the moment the results seem to be quite ok. I am facing now with the 1$ question :
"how to monitor the cache and rbd image inside it ?".
I can't quite find some documentation on metrics associated with it, and now my metric
with those image are zero flat ;) . I will keep searching.
Bye the way, thanks for your preceding answer.
Best Regards