On Wed, Apr 27, 2016 at 1:15 PM, Yehuda Sadeh-Weinraub <yehuda@xxxxxxxxxx> wrote: > On Wed, Apr 27, 2016 at 1:02 PM, Abhishek L <abhishek@xxxxxxxx> wrote: >> >> Yehuda Sadeh-Weinraub writes: >> >>> On Tue, Apr 26, 2016 at 3:21 PM, Yehuda Sadeh-Weinraub >>> <yehuda@xxxxxxxxxx> wrote: >>>> On Tue, Apr 26, 2016 at 10:37 AM, Abhishek Lekshmanan <abhishek@xxxxxxxx> wrote: >>>>> >>>>> Abhishek L writes: >>>>> >>>>>> Yehuda Sadeh-Weinraub writes: >>>>>> >>>>>>> On Mon, Apr 25, 2016 at 1:17 AM, Abhishek Lekshmanan <abhishek@xxxxxxxx> wrote: >>>>>>>> >>>>>>>> Yehuda Sadeh-Weinraub writes: >>>>>>>> >>>>>>>>> On Tue, Apr 19, 2016 at 11:08 AM, Yehuda Sadeh-Weinraub >>>>>>>>> <yehuda@xxxxxxxxxx> wrote: >>>>>>>>>> On Tue, Apr 19, 2016 at 10:54 AM, Abhishek L >>>>>>>>>> <abhishek.lekshmanan@xxxxxxxxx> wrote: >>>>>>>>>>> >>>>>>>>>>> Yehuda Sadeh-Weinraub writes: >>>>>>>>>>> >>>>>>>>>>>> On Tue, Apr 19, 2016 at 9:10 AM, Abhishek Lekshmanan <abhishek@xxxxxxxx> wrote: >>>>>>>>>>>>> Trying deleting objects & buckets from a secondary zone in a RGW >>>>>>>>>>>>> multisite configuration leads to some wierdness: >>>>>>>>>>>>> >>>>>>>>>>>>> 1. On deleting an object and the bucket immediately will mostly lead to >>>>>>>>>>>>> object and bucket getting deleted in the secondary zone, but since we >>>>>>>>>>>>> forward the bucket deletion to master only after we delete in secondary >>>>>>>>>>>>> it will fail with 409 (BucketNotEmpty) and gets reraised as a 500 to the >>>>>>>>>>>>> client. This _seems_ simple enough to fix if we forward the bucket >>>>>>>>>>>>> deletion request to master zone before attempting deletion locally, >>>>>>>>>>>>> (issue: http://tracker.ceph.com/issues/15540, possible fix: https://github.com/ceph/ceph/pull/8655) >>>>>>>>>>>>> >>>>>>>>>>>> >>>>>>>>>>>> Yeah, this looks good. We'll get it through testing. >>>>>>>>>>>> >>>>>>>>>>>>> 2. Deletion of objects themselves: deletion of objects themselves seems >>>>>>>>>>>>> to be a bit racy, deleting an object on a secondary zone succeeds, >>>>>>>>>>>>> listing the bucket seems to show an empty list, but gets populated with >>>>>>>>>>>>> the object again sometimes (this time with a newer timestamp), this is >>>>>>>>>>>>> not always guaranteed to be reproduce, but I've seen this often with >>>>>>>>>>>>> multipart uploads, as an eg: >>>>>>>>>>>>> >>>>>>>>>>>>> $ s3 -u list test-mp >>>>>>>>>>>>> Key Last Modified Size >>>>>>>>>>>>> -------------------------------------------------- -------------------- ----- >>>>>>>>>>>>> test.img 2016-04-19T13:00:17Z 40M >>>>>>>>>>>>> $ s3 -u delete test-mp/test.img >>>>>>>>>>>>> $ s3 -u list test-mp >>>>>>>>>>>>> Key Last Modified Size >>>>>>>>>>>>> -------------------------------------------------- -------------------- ----- >>>>>>>>>>>>> test.img 2016-04-19T13:00:45Z 40M >>>>>>>>>>>>> $ s3 -u delete test-mp/test.img # wait for a min >>>>>>>>>>>>> $ s3 -us list test-mp >>>>>>>>>>>>> -------------------------------------------------- -------------------- ----- >>>>>>>>>>>>> test.img 2016-04-19T13:01:52Z 40M >>>>>>>>>>>>> >>>>>>>>>>>>> >>>>>>>>>>>>> Mostly seeing log entries of this form in both the cases ie. where >>>>>>>>>>>>> delete object seems to be successfully delete in both master and >>>>>>>>>>>>> secondary zone and the case where it succeeds in master and fails in >>>>>>>>>>>>> secondary : >>>>>>>>>>>>> >>>>>>>>>>>>> 20 parsed entry: id=00000000027.27.2 iter->object=foo iter->instance= name=foo instance= ns= >>>>>>>>>>>>> 20 [inc sync] skipping object: dkr:d8e0ec3d-b3da-43f8-a99b-38a5b4941b6f.14113.2:-1/foo: non-complete operation >>>>>>>>>>>>> 20 parsed entry: id=00000000028.28.2 iter->object=foo iter->instance= name=foo instance= ns= >>>>>>>>>>>>> 20 [inc sync] skipping object: dkr:d8e0ec3d-b3da-43f8-a99b-38a5b4941b6f.14113.2:-1/foo: canceled operation >>>>>>>>>>>>> >>>>>>>>>>>>> Any ideas on this? >>>>>>>>>>>>> >>>>>>>>>>>> >>>>>>>>>>>> Do you have more than 2 zones syncing? Is it an object delete that >>>>>>>>>>>> came right after the object creation? >>>>>>>>>>> >>>>>>>>>>> Only 2 zones ie. one master and one secondary, req, on secondary. The delete came right after the >>>>>>>>>>> create though >>>>>>>>>> >>>>>>>>>> There are two issues that I see here. One is that we sync an object, >>>>>>>>>> but end up with different mtime than the object's source. The second >>>>>>>>>> issue is that we shouldn't have synced that object. >>>>>>>>>> >>>>>>>>>> There needs to be a check when syncing objects, to validate that we >>>>>>>>>> don't sync an object that originated from the current zone (by >>>>>>>>>> comparing the short zone id). We might be missing that. >>>>>>>>>> >>>>>>>>> >>>>>>>>> For the first issue, see: >>>>>>>>> https://github.com/ceph/ceph/pull/8685 >>>>>>>>> >>>>>>>>> However, create that follows by a delete will still be a problem, as >>>>>>>>> when we sync the object we check it against the source mtime is newer >>>>>>>>> than the destination mtime. This is problematic with deletes, as these >>>>>>>>> don't have mtime once the object is removed. I think the solution >>>>>>>>> would be by using temporary tombstone objects (we already have the olh >>>>>>>>> framework that can provide what we need), that we'll garbage collect. >>>>>>>> >>>>>>>> Further information from logs if it helps: >>>>>>>> >>>>>>>> 2016-04-19 17:00:45.539356 7fc99effd700 0 _send_request(): deleting obj=test-mp:test.img >>>>>>>> 2016-04-19 17:00:45.539902 7fc99effd700 20 _send_request(): skipping object removal obj=test-mp:test.img (obj mtime=2016-04-19 17:00:26.0.098255s, request timestamp=2016-04-19 17:00:17.0.395208s) >>>>>>>> >>>>>>>> This is what the master zone logs show, however the request timestamp >>>>>>>> logged here is the `If-Modified-Since` value from secondary zone when >>>>>>>> the actual object write was completed (and not the time when deletion >>>>>>>> was completed), do we set the value of the deletion time anywhere else >>>>>>>> in the BI log >>>>>>>> >>>>>>>> >>>>>>> >>>>>>> Did you apply PR 8685? >>>>>>> >>>>>>> Also, take a look at this: >>>>>>> >>>>>>> https://github.com/ceph/ceph/pull/8709 >>>>>>> >>>>>>> With the new code we do store the object creation time in the delete >>>>>>> bucket index entry. That way we make sure we only sync object removal, >>>>>>> if the object was the same or older than the one that was actually >>>>>>> removed. >>>>> >>>>> Applied both PRs atop of master + 8655, basically now the object doesn't >>>>> resync back to the secondary zone after deletion which we observed >>>>> before.A create followed by an immediate delete succeeds delete in both the >>>>> zones almost every time. >>>>> >>>>> However allowing the object to sync to primary by introducing a delay, >>>>> for eg a script on secondary like: >>>>> >>>>> for i in {1..20}; do s3 -us put foobar/foo$i filename=test.img && sleep 3 && s3 -us delete foobar/foo$i; done >>>>> >>>>> gives a empty list on the secondary zone, on the primary zone however it >>>>> looks like very few objects got actually deleted and others are still existing >>>>> >>>>> $ s3 -us list foobar >>>>> Content-Type: application/xml >>>>> Request-Id: tx000000000000000001db8-00571f9cdb-1015-us-east-1 >>>>> Content-Length: 4713 >>>>> Key Last Modified Size >>>>> -------------------------------------------------- -------------------- ----- >>>>> foo1 2016-04-26T14:24:25Z 87M >>>>> foo10 2016-04-26T14:27:28Z 87M >>>>> foo11 2016-04-26T14:27:50Z 87M >>>>> foo12 2016-04-26T14:28:12Z 87M >>>>> foo14 2016-04-26T14:28:48Z 87M >>>>> foo15 2016-04-26T14:29:09Z 87M >>>>> foo16 2016-04-26T14:29:30Z 87M >>>>> foo17 2016-04-26T14:29:51Z 87M >>>>> foo18 2016-04-26T14:30:12Z 87M >>>>> foo19 2016-04-26T14:30:33Z 87M >>>>> foo2 2016-04-26T14:24:47Z 87M >>>>> foo20 2016-04-26T14:30:54Z 87M >>>>> foo3 2016-04-26T14:25:07Z 87M >>>>> foo6 2016-04-26T14:26:05Z 87M >>>>> foo7 2016-04-26T14:26:24Z 87M >>>>> foo8 2016-04-26T14:26:47Z 87M >>>>> foo9 2016-04-26T14:27:07Z 87M >>>>> >>>>> Logs show this in case of failed deletes: >>>>> 2016-04-26 18:31:01.793673 7ff3f1ffb700 10 If-UnModified-Since: 2016-04-26 18:30:54.0.751623s Last-Modified: 0.000000 >>>>> 2016-04-26 18:31:01.793716 7ff3f1ffb700 20 _send_request(): delete_obj() obj=foobar3:foo20 returned ret=-2 >>>>> >>>>> In case of an object that succeeded deletion: >>>>> 2016-04-26 18:28:40.673885 7ff3f27fc700 10 If-UnModified-Since: 2016-04-26 18:28:30.0.510155s Last-Modified: 2016-04-26 18:28:30.510155 >>>>> >>>>> More interesting log: >>>>> 2016-04-26 18:25:52.660674 7ff3cf7fe700 10 If-UnModified-Since: 2016-04-26 18:25:46.0.700052s Last-Modified: 0.000000 >>>>> 2016-04-26 18:25:52.660698 7ff3cf7fe700 20 _send_request(): delete_obj() obj=foobar3:foo5 returned ret=-2 >>>>> ... >>>>> 2016-04-26 18:25:59.341420 7ff3a67fc700 10 If-UnModified-Since: 2016-04-26 18:25:46.0.700052s Last-Modified: 2016-04-26 18:25:46.700052 >>>>> [this was object foo5.. which was one of the objects that got deleted] >>>>> >>>>> Let me know if any other log info may be helpful (only debug rgw was >>>>> set, debug ms was 0) >>>> >>>> Yes, this would be great. If you could provide log with 'debug rgw = >>>> 20' and 'debug ms = 1' it'd be helpful. I'm trying to reproduce the >>>> issue, and was able to get some bad behavior, but different than what >>>> you describe. >> >> Tried reproducing this behaviour again, not very successful though, I >> have debug logs without debug ms setting. >>> >>> Please take a look at PR 8772, and let me know whether things work >>> differently for you. >>> >> Still seeing the old issue (with or without 8772), ie. master sees an >> object and even though it is deleted in secondary after sometime it >> reappears. I've uploaded logs of both the regions using >> `ceph-post-file`, uid cc9207f5-8aad-4f29-8d2a-6b84f2c253b0 >> > > > Still haven't looked at the logs, but a quick question. Did you also > update the osds with the changes in these PRs? There is an objclass > change there, so the osd side needed to be updated and restarted. > Ok, after looking at the logs, I think I understand the problem. For some reason object deletes sync can happen in concurrent with object creation. I'll fix that and update the PR. Thanks, Yehuda -- 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
