On Sat, 2009-04-18 at 12:47 +0200, Dietmar Maurer wrote: > > > Is there any guarantee that all sections inside a recovered > > checkpoint > > > are from the same cluster partition (I can't see such restriction in > > the > > > algorithm)? > > > > > > > no > > > > The algorithm will merge sections created in both partitions into the > > single checkpoint. > > At least the SA Forum does not mention such strange behavior. Isn't that > a serious bug? > > Consider 2 Partitions with one checkpoint: > > Part1: CkptSections ABC > Part2: CkptSections BCD > > After the merge, you have: CkptSections ABCD > > And even worse, section contains data from different partitions (old > data mixed with new one)? And there is no notification that such things > happens? >
The SA Forum doesn't consider at all how to handle partitions in a network or at least not very suitably (up to designer of SA Forum services). They assume that applications will be using the AMF, and rely on the AMF functionality to reboot partitioned nodes (fencing) so this condition doesn't occur. The SA Forum services were not designed with partitioned networks in mind. It is unfortunate, but it is what it is. If an app needs true consistently without some form of fencing, the app designer has to take partitions into consideration when designing their applications. This is why I recommend using CPG for these types of environments because it provides better design control over exactly how data remerges. Regards -steve > - Dietmar > _______________________________________________ Openais mailing list Openais@lists.linux-foundation.org https://lists.linux-foundation.org/mailman/listinfo/openais
