High iops on default.rgw.buckets.index

Hi all. About 2 days my Ceph cluster goes 1 millions IO/s on reads default.rgw.buckets.index. When this happens my PUT requests goes up to 200 req/s but I had 500 req/s before and there were no high IO/s on that pool. When this happens my rgw nodes and OSDs goes up to 100% cpu usage. Do you have any indea what’s going on here that this pool gets 1 millions IO/s? Also I have upgraded to 14.2.8 but problem still persists. Thanks for you help :)