Hi Andrew,
That's a lovely solution. Is this functionality part of your
frameworks? (besides the JSON-RPC-stuff)
I also like the distributed aspect, that could be useful in my case.
Besides, you planted a seed in my brain - now my fingers are itching
to write something like a simple Xgrid-style server/client to perform
distributed EOF-operations. :-)
Cheers,
- Hugi
PS: Heh, class names like that happen after midnight :-).
// Hugi Thordarson
// http://hugi.karlmenn.is/
On 10.1.2009, at 11:13, Andrew Lindesay wrote:
Hello Hugi;
"KMMassiveOperation" <--- that's a really great class name.
What I do is to pull GID's or PK's for all of the objects involved
using raw rows. As you say, sometimes the data sets are large
enough that I have to further subdivide them on a domain-specific
basis, but I won't complicate matters further... In any case, I get
lots of GID's or PK's. Then I batch them up into (for example) lots
of 100 or so and then farm the work-load out over JMS (more recently
using JSON-RPC through a "JMS adaptor") so that the processing is
able to run concurrently over a number of instances on a number of
hosts. The number of instances involved increases the concurrency
and hence the pressure on the database system. In the case of
writing out CSV or Excel-readable XML files, I push the results from
the workers into a "BLOB stream" -- effectively just a series of
BLOBs that make up one long piece of contiguous data. The control
and monitoring systems for all this are quite complex, but it does
work well and I can do it all in EOF without resorting to SQL.
cheers.
Anyway, I would love to hear how other folks are handling huge
datasets. I would love fedback on the technique I'm using, and ieas
for improvement would be great. Just about the only idea I'm not
open to is "just use JDBC" ;-). I've been there and I don't want to
be there. That's why I'm using EOF :-).
___
Andrew Lindesay
www.lindesay.co.nz
_______________________________________________
Do not post admin requests to the list. They will be ignored.
Webobjects-dev mailing list ([email protected])
Help/Unsubscribe/Update your Subscription:
http://lists.apple.com/mailman/options/webobjects-dev/archive%40mail-archive.com
This email sent to [email protected]
