On Thu, Dec 8, 2011 at 5:11 AM, datanucleus <andy_jeffer...@yahoo.com>wrote:
> > Well, it sounds so. But does (or can/will) Datanucleus support at least
> > some of the features Jeff has mentioned?
>
> Yes, several actually. And nothing is "dog slow", ... though why dogs
> get such a bad reputation I've no idea; take a greyhound for
> example ... :-)
>
> The question was "is caching in DataNucleus simple and transparent";
> that's the question I answered.
>
I'm sorry, but you clearly haven't actually used this cache in the real
world. I've looked at DataNucleus' Level2Cache interface and noticed that
it serializes requests entity-by-entity. This means that every single
request in a batch get triggers 1 or 2 RPCs; on a cold cache, a batch get
for 10 items will require 20 separate, linear RPCs. This doesn't work -
it's an order of magnitude slower than a simple datastore fetch would have
been in the first place.
I have already stumbled across this problem and had to delay releasing
Objectify 3.1 until GAE supported the batch CAS operations that make CAS
caching efficient. I had to delay upgrading one of my real-world products
because of this issue.
So no, datanucleus caching is not simple and transparent if your
application makes use of batch fetching (ie, what should be the most
important operation in most applications).
Not sure also why people always want to make things into a "mines
> better than yours contest". The only statements you'll see from me on
> here are in answer to specific questions about software that uses
> DataNucleus (and Googles plugin does that, with the emphasis on being
> owned by Google, and not being part of the DataNucleus project), with
> the attempt to aid that person use the software better.
You've dumped a bunch of marketing BS in this thread ("nothing could be
simpler!") which does not accurately reflect reality, which is complicated
and messy. It's not personal, and it's not even because I work on a
competing project - it's just that I happen to know a lot about this
particular subject. If you were hawking any kind of software and I
happened to know "the truth behind the marketing", I would call you out on
it.
It does, however, irritate me. It takes up some of my time to rebut these
issues (see the thread on "Slim3 is fast!"). It takes a few minutes to
post a poorly thought out marketing claim or create a half-baked benchmark.
It takes actual research to figure out exactly what's wrong with them.
Your sloppy thinking generates real work for me.
Nowhere have I
> ever made any comment on Objectify's capabilities or made any
> criticism of it (or of similar software, such as Twig, Morphia) -
> perhaps due to the fact that I understand only too well how much time
> and effort is taken to develop something of that form. All software
> has particular features, and their own advantages and
> disadvantages ... DataNucleus (and Google's plugin) has plenty of
> things going for it, as does Objectify. It's for the user to choose
> what best fits *their* requirements using their judgement, not for
> people to spend time criticising.
>
Let's just make sure those users are well and accurately informed.
Jeff
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