Cos, good questions! My answers are inline... On Tue, Apr 18, 2017 at 4:17 PM, Konstantin Boudnik <c...@apache.org> wrote:
> Great news indeed! Thanks for sharing! > > Before we jump on the voting and all that, can we have a chance to learn > more > about this new feature and its integration points with the rest of the > platform? A few questions come to mind immediately: > > 1. This is an "optional disk layer", so it could be turned off > _completely_ and > have no effect on those who don't want nor need to use it, right? > Yes > 2. Does it have any performance implications on the in-memory operations? > No, as long as the persistence is turned off, the in-memory operations will not be impacted. > 3. When you say it is "fully ... ANSI-99 SQL compliant fault-tolerant" > does it > mean that _all_ SQL operations are now now supported through SQL or > still > some of them only available through the JAVA APIs? THe fault tolerance > is > for the data-center only as before, right? No new WAN-able HA has been > introduced? > Well... I would say most SQL operations are going to be supported, including CREATE, DROP, INSERT, UPDATE, DELETE, SELECT, and of course, distributed joins. And yes, you are right about the fault tolerance. > 4. With addition of this new model, are there any backward compatibility > issues that would affect Ignite's application developers? > I don't think so. All incompatible changes should have been introduced in 2.0. I will let other community members comment here... > 5. Can we have a discussion about the design of this new layer so people > here > can understand better what's being offered, how to take the advantage of > it, and - most importantly - to offer their own insights and > improvements > into this new subsystems before it's landed in the source code? And it > would safe a lot of time on Q&A as well. > Yes, good idea. Denis, do you have a high level architecture for the proposed persistence? > > I am confused a little bit by these two slightly controversial statements: > - "GG... has been developing a unique distributed persistent store...for > more > than a year in-house" > - "we decided at GridGain that this tremendous feature should be open > source > from the very beginning" > > So, it sounds like the code has been under the development for a while and > it > isn't opened up "from the very beginning", unless there's a new meaning of > the > word beginning I am not aware of just yet :) It feels like this could be a > significant amount of the code to be digested by the community. > Yes, you are right. Many of us wanted to open source this functionality from the get go. In any case, this makes a great addition to the project. I hope we will be able to provide enough documentation and feedback on the dev list to ease up the digestion process. > > Appreciate your thoughts on this! Thanks, > Cos > > On Mon, Apr 17, 2017 at 07:37PM, Denis Magda wrote: > > Igniters, > > > > GridGain, as one of the most active Apache Ignite contributors, has been > > developing a unique distributed persistent store specifically for Apache > > Ignite for more than a year in-house. It’s a fully ACID and ANSI-99 SQL > > compliant fault-tolerant solution. > > > > The store transparently integrates with Apache Ignite as an optional disk > > layer (in addition to the existing RAM layer) via the new page memory > > architecture that to be released in Apache Ignite 2.0. This allows > storing > > supersets of data on disk while having a subset in memory not worrying > about > > that you forgot to preload (warmup) your caches! > > > > Assuming that the storage goes to ASF as a part of Apache Ignite 2.1 > release > > the following will be supported by Ignite out-of-the-box: > > > > * SQL queries execution over the data that is both in RAM and on disk: no > > need to preload the whole data set in memory. > > > > * Cluster instantaneous restarts: once your cluster ring is recovered > after > > a restart your applications are fully operational even if they highly > > utilize SQL queries. > > > > As for the use cases, it means that Apache Ignite will be possible to > use as > > a distributed SQL database with memory-first concept. > > > > And we decided at GridGain that this tremendous feature should be open > > source from the very beginning. > > > > Guys, could you advise how I can start official donation process? > > > > — > > Denis > > > > > > > > > > > > >
