On Thu, May 27, 2021 at 9:21 AM Andres Rojas Guerrero <a.rojas@csic.es> wrote:
El 26/5/21 a las 16:51, Dan van der Ster escribió:
I see you have two active MDSs. Is your cluster more stable if you use only one single active MDS?
Good question!! I read form Ceph Doc:
"You should configure multiple active MDS daemons when your metadata performance is bottlenecked on the single MDS that runs by default."
"Workloads that typically benefit from a larger number of active MDS daemons are those with many clients, perhaps working on many separate directories."
I have more or less 25 concurrent clients, but working in the same directory, Is that number a lot of clients?
And I assumed that two are always better than one.
25 isn't many clients, but if they are operating in the same directory it will create a lot of contention between the two MDSs, which might explain some of the issues you observe. I recommend that you reduce back to 1 active mds and observe the system stability and performance. -- dan