Hi, Am 01.03.2013 um 13:47 schrieb Michael Dürig:
> > > What Jukka is saying is that the repository gives you a choice between > consistency and availability. Since both you cannot have. I think you don't want to given the user that choice ... I'd opt for best possible availability (or probably you mean performance?) with "guaranteed" consistency. Regards Felix > > Michael > > On 1.3.13 12:40, Felix Meschberger wrote: >> So you essentially say: Behaviour of the repository is "best effort" and we >> -- at the end of the day -- cannot trust the repository ? >> >> Sounds frightening. >> >> IMHO the repository should be failsafe and thus eventually solve the issue >> making sure we don't end up with two copies of the same node (actually both >> copies, if referenceable, will even have the same node ID.... >> >> Regards >> Felix >> >> Am 27.02.2013 um 16:35 schrieb Jukka Zitting: >> >>> Hi, >>> >>> On Wed, Feb 27, 2013 at 5:09 PM, Carsten Ziegeler <[email protected]> >>> wrote: >>>> How will this be handled with Oak? Could it happen that due to this >>>> happening concurrently that the node ends up twice in the repository >>>> (at /1/node and /2/node in my example)? >>> >>> The behavior depends on the underlying MicroKernel implementation. >>> >>> With the new SegmentMK I've been working on, you can control the behavior: >>> >>> * If both cluster nodes use the same (root) journal, then only one of >>> them succeeds and the other one will fail with an exception. The >>> behavior is more or less the same as with current Jackrabbit. >>> >>> * If the cluster nodes use different journals (with background >>> merging), then one of the moves will succeed and depending on timing >>> the other one either fails or ends up producing a duplicate copy of >>> the tree. >>> >>> The latter option is designed to boost write concurrency in scenarios >>> where it's OK for some operations to get lost or produce somewhat >>> inconsistent results (high-volume commenting or logging systems, >>> etc.). Operations for which such behavior is not desirable should use >>> the first option. >>> >>> BR, >>> >>> Jukka Zitting >> >> >> -- >> Felix Meschberger | Principal Scientist | Adobe >> >> >> >> >> >> >> -- Felix Meschberger | Principal Scientist | Adobe
