Sounds good...for your (b) I see that a traverser would easily do it, or I may do it client-side to show stubs for hidden comments. I'll also want (a), a global list of high-rated comments, which is why I'm thinking I'd maintain a list of the top 1000 or so. Comment ratings will degrade over time so nodes should drop out of this list.
I'll want to do something like give a user a sum of the points he's accrued across his comments...assuming worst case of a couple thousand comments, would I likely be better off updating his sum whenever a comment of his is rated, or simply traversing his comments and summing them up when I need to? In the event that I'm very lucky and need more than 200 transactions/s, would it work better to do updates in batches every few seconds? (Of course I guess then I'd need to temporarily save the update instructions somewhere outside the system.) Getting ahead of myself a bit: anything noteworthy about ram requirements? On 6/16/09, Johan Svensson <[email protected]> wrote: > Hi Dennis, > > As Neil mentioned a well configured batch inserter typically gives you > 5x or higher write speed compared to normal writes running in a > transaction. Batch inserter is there to speed up initial import of > data but judging from the use-cases you presented you will be running > in normal transactional mode. > > In a large transaction (thousands of node, relationship and/or > property creates/updates/deletes) you do about 10-100 writes per ms. > Running small write transactions with just a few updates in each > transaction the bottleneck will be the flush operations and then you > typically get around 200 transactions/s (numbers are very hardware > dependent). > > Regarding contention, by default a write will not block a read but > writes have to wait for each other. Modifying a node's or > relationship's properties will acquire a write lock on that node or > relationship holding it until the transaction commits or gets rolled > back. Deleting or creating a relationship will acquire a write lock on > the relationship, the start node and the end node. > > I think you are on the right track considering using Neo4j for this > problem :) If you could give us some more information about how > exactly the rating system is going to work we could advice you on how > to design your graph. For example: > > Does getting the highest rated comments mean: > > a) of all the latest comments since time X, give me the ones that had > the highest rating > > or > > b) for this topic / thread, only show comments with rating higher then X > > Regards, > Johan > _______________________________________________ Neo mailing list [email protected] https://lists.neo4j.org/mailman/listinfo/user
