Dear ceph users, I like to get some clarification regarding the Fast-EC BUG in tentacle[1]. The clyso article mentions "on CephFS", which gave the impression that just CephFS as a application is affected, but others like RBD are not. I assume and may found out, that RDB is also affected. In a cephadm test environment I started a qemu-VM on an EC-data-pool with ec-overwrite and ec-optimisations set and issued fstrim (qemu discard=unmap via librbd) which immediately brings down some OSDs (see log below). Also the clyso article points to issue 71642 "crash if allow_ec_optimizations set but with allow_ec_overwrites not set"[2], which from its title seems misleading because others and I have allow_ec_overwrites set. Thanks to clyso's known-bugs collection! Otherwise it's hard to get an overview what problem one might hit currently ;-). And also thanks for providing fixed images on harbor.clyso.com/custom-ceph/ceph/ceph:v20.2.0-fast-ec-path-hf.2. It seems the fix[3] is from Jul 11, 2025, but still awaiting backport to, in the mean time released, stable version tentacle? Sounds odd. Thanks, Sascha. [1] https://docs.clyso.com/docs/kb/known-bugs/tentacle/#osd-crash-when-enabling-... [2] https://tracker.ceph.com/issues/71642 [3] https://github.com/ceph/ceph/commit/51679b948bd9bb45cce9d778b0555f45ff808cd8 ODS crash log ======8<-------------------------- osd-1[197069]: terminate called after throwing an instance of 'std::out_of_range' osd-1[197069]: what(): Key not found osd-1[197069]: *** Caught signal (Aborted) ** osd-1[197069]: in thread 7f2dd5c65640 thread_name:tp_osd_tp osd-1[197069]: ceph version 20.2.0 (69f84cc2651aa259a15bc192ddaabd3baba07489) tentacle (stable - RelWithDebInfo) osd-1[197069]: 1: /lib64/libc.so.6(+0x3fc30) [0x7f2df4da8c30] osd-1[197069]: 2: /lib64/libc.so.6(+0x8d03c) [0x7f2df4df603c] osd-1[197069]: 3: raise() osd-1[197069]: 4: abort() osd-1[197069]: 5: /lib64/libstdc++.so.6(+0xa1b21) [0x7f2df5b45b21] osd-1[197069]: 6: /lib64/libstdc++.so.6(+0xad53c) [0x7f2df5b5153c] osd-1[197069]: 7: /lib64/libstdc++.so.6(+0xad5a7) [0x7f2df5b515a7] osd-1[197069]: 8: /lib64/libstdc++.so.6(+0xad809) [0x7f2df5b51809] osd-1[197069]: 9: /usr/bin/ceph-osd(+0x41b012) [0x55ef3f2b1012] osd-1[197069]: 10: (ECTransaction::WritePlanObj::WritePlanObj(hobject_t const&, PGTransaction::ObjectOperation const&, ECU> osd-1[197069]: 11: /usr/bin/ceph-osd(+0x99cdaa) [0x55ef3f832daa] osd-1[197069]: 12: (ECCommon::get_write_plan(ECUtil::stripe_info_t const&, PGTransaction&, ECCommon::ReadPipeline&, ECComm> osd-1[197069]: 13: (ECBackend::submit_transaction(hobject_t const&, object_stat_sum_t const&, eversion_t const&, std::uniq> osd-1[197069]: 14: /usr/bin/ceph-osd(+0x7d980f) [0x55ef3f66f80f] osd-1[197069]: 15: (PrimaryLogPG::issue_repop(PrimaryLogPG::RepGather*, PrimaryLogPG::OpContext*)+0x3ae) [0x55ef3f5f002e] osd-1[197069]: 16: (PrimaryLogPG::execute_ctx(PrimaryLogPG::OpContext*)+0xf6a) [0x55ef3f5cd63a] osd-1[197069]: 17: (PrimaryLogPG::do_op(boost::intrusive_ptr<OpRequest>&)+0x2d5f) [0x55ef3f5bdf5f] osd-1[197069]: 18: (OSD::dequeue_op(boost::intrusive_ptr<PG>, boost::intrusive_ptr<OpRequest>, ThreadPool::TPHandle&)+0x19> osd-1[197069]: 19: (ceph::osd::scheduler::PGOpItem::run(OSD*, OSDShard*, boost::intrusive_ptr<PG>&, ThreadPool::TPHandle&)> osd-1[197069]: 20: (OSD::ShardedOpWQ::_process(unsigned int, ceph::heartbeat_handle_d*)+0x8bc) [0x55ef3f51611c] osd-1[197069]: 21: (ShardedThreadPool::shardedthreadpool_worker(unsigned int)+0x23a) [0x55ef3fa98e1a] osd-1[197069]: 22: /usr/bin/ceph-osd(+0xc033d4) [0x55ef3fa993d4] osd-1[197069]: 23: /lib64/libc.so.6(+0x8b2fa) [0x7f2df4df42fa] osd-1[197069]: 24: /lib64/libc.so.6(+0x110400) [0x7f2df4e79400] osd-1[197069]: 2026-02-15T00:10:48.350+0000 7f2dd5c65640 -1 *** Caught signal (Aborted) ** osd-1[197069]: in thread 7f2dd5c65640 thread_name:tp_osd_tp --------------------------------------