Streaming Processing of Large XML Data Jana Dvořáková, Filip Zavoral processing of large XML data using XSLT with optimal memory complexity formal model / implementation framework analyzer, SSXT / BUXT transformer

SSXT - streaming transducer Simple Streaming Xml Transducer no backward axis, no predicates, no variables order-preserving branch-disjoint  stack / document depth BUXT - Buffering Transducer

Xord framework - Analyzer Analyzer XSLT & XSD: virtually applies templates to schema all possible node sequences are processed regexp all possible node sequences selected by XPath expressions possible reading orders of the elements names sequence of element names in the order they are called represents the processing order of the elements

SSXT Transformer Polymorphic stack –two types of transformation states - DFA & CC –related to current document level sequence of deterministic finite automata states –concurrent evaluation of XPath expressions –single DFA for each expression –start-tag → DFA transition –final state → template call cycle configuration –template and template call being processed

Evaluation & Comparison Memory consumption (MB) of SSXT algorithm and tree-based XSLT processors for input XML data of different size DBLP.xml ≈ 700 MB

Future work –buffering transformer optimizations and evaluation –multipass streaming algorithms –overcoming some restrictions to XSLT constructs Future work