Get children of a node faster

I'm using the alfresco api on my Java backed webscript. I have an uuid, and I do a new NodeRef with this uuid and then I use getChildAssoc from nodeService to obtain all the direct child nodes.

NodeRef nodeRef =new NodeRef("workspace://SpacesStore/"+ uuid);
List<ChildAssociationRef> childRefList =new ArrayList<ChildAssociationRef>();
    childRefList = getNodeService().getChildAssocs(nodeRef); 
for(ChildAssociationRef childRef : childRefList){
    NodeRef nodeChildRef = childRef.getChildRef();
    ...
}

But on folders with more than 100 subfolders it takes too long. Are there another quicky way to obtain all direct children of a node? The fastest method you know to do that.

Thanks!