Well, they are actually different types with different encodings and different contents. The client doesn't really have the information needed to build a MSG_OSD_REPOP. Your best bet will be to send an MOSDOp to the replicas and hack up a write path that makes that work. How do you plan to address the consistency problems? -Sam On Thu, Jul 21, 2016 at 11:11 AM, Sugang Li <sugangli@xxxxxxxxxxxxxxxxxx> wrote: > So, to start with, I think one naive way is to make the replica think > it receives an op from the primary OSD, which actually comes from the > client. And the branching point looks like started from > OSD::dispatch_op_fast, where handle_op or handle_replica_op is called > based on the type of the request. So my question is, at the client > side, is there a way that I could set the corresponding variables > referred by "op->get_req()->get_type()" to MSG_OSD_SUBOP or > MSG_OSD_REPOP? > > Sugang > > On Thu, Jul 21, 2016 at 12:03 PM, Samuel Just <sjust@xxxxxxxxxx> wrote: >> Parallel read will be a *lot* easier since read-from-replica already >> works. Write to replica, however, is tough. The write path uses a >> lot of structures which are only populated on the primary. You're >> going to have to hack up most of the write path to bypass the existing >> replication machinery. Beyond that, maintaining consistency will >> obviously be a challenge. >> -Sam >> >> On Thu, Jul 21, 2016 at 8:49 AM, Sugang Li <sugangli@xxxxxxxxxxxxxxxxxx> wrote: >>> My goal is to achieve parallel write/read from the client instead of >>> the primary OSD. >>> >>> Sugang >>> >>> On Thu, Jul 21, 2016 at 11:47 AM, Samuel Just <sjust@xxxxxxxxxx> wrote: >>>> I may be misunderstanding your goal. What are you trying to achieve? >>>> -Sam >>>> >>>> On Thu, Jul 21, 2016 at 8:43 AM, Samuel Just <sjust@xxxxxxxxxx> wrote: >>>>> Well, that assert is asserting that the object is in the pool that the >>>>> pg operating on it belongs to. Something very wrong must have >>>>> happened for it to be not true. Also, replicas have basically none of >>>>> the code required to handle a write, so I'm kind of surprised it got >>>>> that far. I suggest that you read the debug logging and read the OSD >>>>> op handling path. >>>>> -Sam >>>>> >>>>> On Thu, Jul 21, 2016 at 8:34 AM, Sugang Li <sugangli@xxxxxxxxxxxxxxxxxx> wrote: >>>>>> Yes, I understand that. I was introduced to Ceph only 1 month ago, but >>>>>> I have the basic idea of Ceph communication pattern now. I have not >>>>>> make any changes to OSD yet. So I was wondering what is purpose of >>>>>> this "assert(oid.pool == static_cast<int64_t>(info.pgid.pool()))", and >>>>>> to change the code in OSD, what are the main aspects I should pay >>>>>> attention to? >>>>>> Since this is only a research project, the implementation does not >>>>>> have to be very sophisticated. >>>>>> >>>>>> I know my question is kinda too broad, any hints or suggestions will >>>>>> be highly appreciated. >>>>>> >>>>>> Thanks, >>>>>> >>>>>> Sugang >>>>>> >>>>>> On Thu, Jul 21, 2016 at 11:22 AM, Samuel Just <sjust@xxxxxxxxxx> wrote: >>>>>>> Oh, that's a much more complicated change. You are going to need to >>>>>>> make extensive changes to the OSD to make that work. >>>>>>> -Sam >>>>>>> >>>>>>> On Thu, Jul 21, 2016 at 8:21 AM, Sugang Li <sugangli@xxxxxxxxxxxxxxxxxx> wrote: >>>>>>>> Hi Sam, >>>>>>>> >>>>>>>> Thanks for the quick reply. The main modification I made is to call >>>>>>>> calc_target within librados::IoCtxImpl::aio_operate before op_submit, >>>>>>>> so that I can get all replicated OSDs' id, and send a write op to each >>>>>>>> of them. I can also attach the modified code if necessary. >>>>>>>> >>>>>>>> I just reproduced this error with the conf you provided, please see below: >>>>>>>> osd/ReplicatedPG.cc: In function 'int >>>>>>>> ReplicatedPG::find_object_context(const hobject_t&, ObjectContextRef*, >>>>>>>> bool, bool, hobject_t*)' thread 7fd6aba59700 time 2016-07-21 >>>>>>>> 15:09:26.431436 >>>>>>>> osd/ReplicatedPG.cc: 9042: FAILED assert(oid.pool == >>>>>>>> static_cast<int64_t>(info.pgid.pool())) >>>>>>>> ceph version 10.2.0-2562-g0793a28 (0793a2844baa38f6bcc5c1724a1ceb9f8f1bbd9c) >>>>>>>> 1: (ceph::__ceph_assert_fail(char const*, char const*, int, char >>>>>>>> const*)+0x8b) [0x7fd6c5733e8b] >>>>>>>> 2: (ReplicatedPG::find_object_context(hobject_t const&, >>>>>>>> std::shared_ptr<ObjectContext>*, bool, bool, hobject_t*)+0x1e54) >>>>>>>> [0x7fd6c51ef7c4] >>>>>>>> 3: (ReplicatedPG::do_op(std::shared_ptr<OpRequest>&)+0x186e) [0x7fd6c521fe9e] >>>>>>>> 4: (ReplicatedPG::do_request(std::shared_ptr<OpRequest>&, >>>>>>>> ThreadPool::TPHandle&)+0x73c) [0x7fd6c51dca3c] >>>>>>>> 5: (OSD::dequeue_op(boost::intrusive_ptr<PG>, >>>>>>>> std::shared_ptr<OpRequest>, ThreadPool::TPHandle&)+0x3f5) >>>>>>>> [0x7fd6c5094d65] >>>>>>>> 6: (PGQueueable::RunVis::operator()(std::shared_ptr<OpRequest> >>>>>>>> const&)+0x5d) [0x7fd6c5094f8d] >>>>>>>> 7: (OSD::ShardedOpWQ::_process(unsigned int, >>>>>>>> ceph::heartbeat_handle_d*)+0x86c) [0x7fd6c50b603c] >>>>>>>> 8: (ShardedThreadPool::shardedthreadpool_worker(unsigned int)+0x947) >>>>>>>> [0x7fd6c5724117] >>>>>>>> 9: (ShardedThreadPool::WorkThreadSharded::entry()+0x10) [0x7fd6c5726270] >>>>>>>> 10: (()+0x8184) [0x7fd6c3b98184] >>>>>>>> 11: (clone()+0x6d) [0x7fd6c1aa937d] >>>>>>>> NOTE: a copy of the executable, or `objdump -rdS <executable>` is >>>>>>>> needed to interpret this. >>>>>>>> 2016-07-21 15:09:26.454854 7fd6aba59700 -1 osd/ReplicatedPG.cc: In >>>>>>>> function 'int ReplicatedPG::find_object_context(const hobject_t&, >>>>>>>> ObjectContextRef*, bool, bool, hobject_t*)' thread 7fd6aba59700 time >>>>>>>> 2016-07-21 15:09:26.431436 >>>>>>>> >>>>>>>> >>>>>>>> This error occurs three times since I wrote to three OSDs. >>>>>>>> >>>>>>>> Thanks, >>>>>>>> >>>>>>>> Sugang >>>>>>>> >>>>>>>> On Thu, Jul 21, 2016 at 10:54 AM, Samuel Just <sjust@xxxxxxxxxx> wrote: >>>>>>>>> Hmm. Can you provide more information about the poison op? If you >>>>>>>>> can reproduce with >>>>>>>>> debug osd = 20 >>>>>>>>> debug filestore = 20 >>>>>>>>> debug ms = 1 >>>>>>>>> it should be easier to work out what is going on. >>>>>>>>> -Sam >>>>>>>>> >>>>>>>>> On Thu, Jul 21, 2016 at 7:13 AM, Sugang Li <sugangli@xxxxxxxxxxxxxxxxxx> wrote: >>>>>>>>>> Hi all, >>>>>>>>>> >>>>>>>>>> I am working on a research project which requires multiple write >>>>>>>>>> operations for the same object at the same time from the client. At >>>>>>>>>> the OSD side, I got this error: >>>>>>>>>> osd/ReplicatedPG.cc: In function 'int >>>>>>>>>> ReplicatedPG::find_object_context(const hobject_t&, ObjectContextRef*, >>>>>>>>>> bool, bool, hobject_t*)' thread 7f0586193700 time 2016-07-21 >>>>>>>>>> 14:02:04.218448 >>>>>>>>>> osd/ReplicatedPG.cc: 9041: FAILED assert(oid.pool == >>>>>>>>>> static_cast<int64_t>(info.pgid.pool())) >>>>>>>>>> ceph version 10.2.0-2562-g0793a28 (0793a2844baa38f6bcc5c1724a1ceb9f8f1bbd9c) >>>>>>>>>> 1: (ceph::__ceph_assert_fail(char const*, char const*, int, char >>>>>>>>>> const*)+0x8b) [0x7f059fe6dd7b] >>>>>>>>>> 2: (ReplicatedPG::find_object_context(hobject_t const&, >>>>>>>>>> std::shared_ptr<ObjectContext>*, bool, bool, hobject_t*)+0x1dbb) >>>>>>>>>> [0x7f059f9296fb] >>>>>>>>>> 3: (ReplicatedPG::do_op(std::shared_ptr<OpRequest>&)+0x186e) [0x7f059f959d7e] >>>>>>>>>> 4: (ReplicatedPG::do_request(std::shared_ptr<OpRequest>&, >>>>>>>>>> ThreadPool::TPHandle&)+0x73c) [0x7f059f916a0c] >>>>>>>>>> 5: (OSD::dequeue_op(boost::intrusive_ptr<PG>, >>>>>>>>>> std::shared_ptr<OpRequest>, ThreadPool::TPHandle&)+0x3f5) >>>>>>>>>> [0x7f059f7ced65] >>>>>>>>>> 6: (PGQueueable::RunVis::operator()(std::shared_ptr<OpRequest> >>>>>>>>>> const&)+0x5d) [0x7f059f7cef8d] >>>>>>>>>> 7: (OSD::ShardedOpWQ::_process(unsigned int, >>>>>>>>>> ceph::heartbeat_handle_d*)+0x86c) [0x7f059f7f003c] >>>>>>>>>> 8: (ShardedThreadPool::shardedthreadpool_worker(unsigned int)+0x947) >>>>>>>>>> [0x7f059fe5e007] >>>>>>>>>> 9: (ShardedThreadPool::WorkThreadSharded::entry()+0x10) [0x7f059fe60160] >>>>>>>>>> 10: (()+0x8184) [0x7f059e2d2184] >>>>>>>>>> 11: (clone()+0x6d) [0x7f059c1e337d] >>>>>>>>>> >>>>>>>>>> And at the client side, I got segmentation fault. >>>>>>>>>> >>>>>>>>>> I am wondering what will be the possible reason that cause the assert fail? >>>>>>>>>> >>>>>>>>>> Thanks, >>>>>>>>>> >>>>>>>>>> Sugang >>>>>>>>>> -- >>>>>>>>>> To unsubscribe from this list: send the line "unsubscribe ceph-devel" in >>>>>>>>>> the body of a message to majordomo@xxxxxxxxxxxxxxx >>>>>>>>>> More majordomo info at http://vger.kernel.org/majordomo-info.html -- To unsubscribe from this list: send the line "unsubscribe ceph-devel" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
