RE: [TM4J-users] slow tm export

[Conal T. <Con...@vu...>]

Thanks Kal!

I opened a transaction before walking my topic map, but sadly it hasn't =
speeded it up at all :-(

Here's the code I used:

	/* get the topic map from the topic map manager */
	var TopicMapManager =3D =
cocoon.getComponent("org.tm4j.tm4web.cocoon.TopicMapManagerComponent");
	var map =3D TopicMapManager.getTopicMap("nzetc");
	cocoon.releaseComponent(TopicMapManager);

	/* write the topic map to a file */
	var walker =3D new Packages.org.tm4j.topicmap.utils.TopicMapWalker();
	var writer =3D new Packages.org.tm4j.topicmap.utils.XTMWriter();
	var file =3D new java.io.File(export_filename);
	var os =3D new java.io.FileOutputStream(file);
	var of =3D new Packages.org.apache.xml.serialize.OutputFormat();
	of.setEncoding("UTF-8");
	of.setIndenting(true);
	of.setIndent(2);
	var serializer =3D new =
Packages.org.apache.xml.serialize.XMLSerializer(os, of);
	walker.setHandler(writer);
	writer.setContentHandler(serializer);
=09
	var txn =3D map.getProvider().openTransaction();
	try {
	  walker.walk(map);
	} finally {
	  txn.abort();
	}
=09
	/* walker.walk(map); */
	cocoon.sendPage("export/nzetc.xtm");

Cheers

Con

> My guess is that the walk is just doing to many transactions. If you
> don't have an "outer" transaction wrapping that walk, then=20
> each call to
> the API will result in a separate transaction against the database -
> which amounts to quite a lot of transactions to walk the whole map.
>=20
> What I would recommend you try is creating a transaction to=20
> wrap around
> the walk. If a transaction is already in progress, then the TM4J
> Hibernate code will use that txn instead of creating one.
>=20
> The code would be something like this:
>=20
> ProviderTransaction txn =3D provider.getTransaction();
> try {
>   walker.walk();
> } finally {
>   txn.abort();
> }