I'm running with oXygen Developer version 13.2 with Saxon-EE 9.3.0.5.  There is no timing option in the configuration dialog page.  My code is as follows:
 

<?xml version="1.0" encoding="UTF-8"?>


<xsl:stylesheet version="2.1"
xmlns:xsl="http://www.w3.org/1999/XSL/Transform"
xmlns:saxon="http://saxon.sf.net/"
xmlns:xsi="http://dummy.instance.net/"
xmlns:xs="http://dummy.schema.net/"
>

<xsl:template match="/">
<xsl:for-each select="saxon:stream(doc('test7.xml')/*/*/table_data)">
<xsl:variable name="table-name" select="@name"/>
<xsl:variable name="collection-uri" select="concat('db/',parent::*/@name,'/',$table-name)"/>
<xsl:for-each select="row">
<xsl:variable name="record">
<xsl:element name="{$table-name}">
<xsl:for-each select="field[@name]">
<xsl:element name="{if(number(substring(@name,1,1))=number(substring(@name,1,1))) then concat('_',@name) else @name}">
<xsl:value-of select="text()"/>
</xsl:element>
</xsl:for-each>
</xsl:element>
</xsl:variable>
<xsl:variable name="id" select="if($record/*/id) then concat('id-',$record/*/id) else concat('ndx-',position())"/>
<xsl:result-document href="{$collection-uri}/{$id}.xml">
<xsl:copy-of select="$record"/>
</xsl:result-document>
</xsl:for-each>
</xsl:for-each>
</xsl:template>
</xsl:stylesheet>

 
This code functions on a file that is 112Megs in size.  It fails on a file that is 527Megs in size. The original export file is 704Megs in size.  The second and third files contain the xsi:type attribute which I've cast the xsi and xs namespaces to dummy hrefs.  A file of 485KB succeeds with these dummy attributes present.  The oXygen debug steps through the stream() function to the doc() function before spinning for a bit and then throwing the Java heap space exception.
 
I have yet to figure out how to extract Saxon from oXygen so as to run in command line mode.  I guess figuring this out is my next task.