Setting the Partition Size
When the enhanced XML parser parses a document, it places the content into fixed-size partitions. While the parser determines the size of the partitions, you can provide guidance to the parser by specifying the partition size. You can only specify partition size when using the pub.xml:loadEnhancedXMLNode service or the pub.xml.xmlStringtoEnhancedMLNode service. Both services have an input parameter named partitionSize. Keep the following points in mind when setting a partition size:
The
partitionSize is a hint for the enhanced XML parser so that it can estimate the amount of heap space needed to parse the document. Often, it not possible to determine the size of an inbound XML document before parsing.
As a general rule,
Software AG recommends a
partitionSize that is 1/2 the size of the unparsed XML document.
A
partitionSize that is considerably larger than 1/2 the size of the unparsed XML document causes the enhanced XML parser to consume more heap space than necessary but might also improve throughput. However, this can impact the overall performance of
Integration Server.
A
partitionSize that is considerably smaller than 1/2 the size of the unparsed XML document causes the enhanced XML parser to create a large number of partitions to parse the document. While this might use less heap space, it may reduce the throughput of the parser.
A
partitionSize that is three times smaller or three times larger than 1/2 the size of the unparsed XML document will likely have little impact on the performance.
At run time, the enhanced XML parser overrides a
partitionSize that consumes all of the available heap space.
At run time, if the
partitionSize results in an initial heap allocation that exceeds the single document limit set in the
Maximum heap allocation for any single document field the limit for all documents set in the
Maximum heap allocation for all documents combined field, the enhanced XML parser reduces the partition size automatically.
If you do not specify
partitionSize, the enhanced XML parser uses the default specified in the
Default partition size field on the
Settings > Enhanced XML Parsing page in
Integration Server Administrator.
When the enhanced XML parser is called via an HTTP POST request, the enhanced XML parser uses the default partition size specified by the Default partition size field on the Settings > Enhanced XML Parsing page in Integration Server Administrator.