Hi, My experience is similar, I was also using elrepo kernels on CentOS 8. Kernels 5.14+ were causing problems, I had to go back to 5.11. I did not test 5.12-5.13. I did not have enough time to narrow down the system instability to Ceph. Currently, I'm using the included Rocky Linux 8 kernels (4.18); I very rarely get caps release warnings but besides that everything has been working great. David On Wed, May 11, 2022, 09:07 Stefan Kooman <stefan@xxxxxx> wrote: > Hi List, > > We have quite a few linux kernel clients for CephFS. One of our > customers has been running mainline kernels (CentOS 7 elrepo) for the > past two years. They started out with 3.x kernels (default CentOS 7), > but upgraded to mainline when those kernels would frequently generate > MDS warnings like "failing to respond to capability release". That > worked fine until 5.14 kernel. 5.14 and up would use a lot of CPU and > *way* more bandwidth on CephFS than older kernels (order of magnitude). > After the MDS was upgraded from Nautilus to Octopus that behavior is > gone (comparable CPU / bandwidth usage as older kernels). However, the > newer kernels are now the ones that give "failing to respond to > capability release", and worse, clients get evicted (unresponsive as far > as the MDS is concerned). Even the latest 5.17 kernels have that. No > difference is observed between using messenger v1 or v2. MDS version is > 15.2.16. > Surprisingly the latest stable kernels from CentOS 7 work flawlessly > now. Although that is good news, newer operating systems come with newer > kernels. > > Does anyone else observe the same behavior with newish kernel clients? > > Gr. Stefan > > _______________________________________________ > ceph-users mailing list -- ceph-users@xxxxxxx > To unsubscribe send an email to ceph-users-leave@xxxxxxx > _______________________________________________ ceph-users mailing list -- ceph-users@xxxxxxx To unsubscribe send an email to ceph-users-leave@xxxxxxx
 |