Method and apparatus for virtualized XML parsing

• US 20070113172A1
• Filed: 11/14/2005
• Published: 05/17/2007
• Est. Priority Date: 11/14/2005
• Status: Active Grant

• Current Assignee: Oracle America, Inc. (Oracle Corporation)
• Original Assignee: Oracle America, Inc. (Oracle Corporation)
• Inventors: Behrens, Jochen, Zaumen, William, Seltzer, Wayne, Dignum, Marcelino
• Granted Patent: US 7,665,016 B2
• Time in Patent Office: Days
• US Class Current: 715/239
• CPC Class Codes: G06F 40/131 Fragmentation of text files, e.g. creating reusable text-blocks; Linking to fragments, e.g. using XInclude; Namespaces
• CPC Class Codes: G06F 40/143 Markup, e.g. Standard Generalized Markup Language [SGML] or Document Type Definition [DTD]

Abstract

A method and apparatus for performing virtualized parsing of an XML document. A document is divided into multiple segments, which may correspond to separate packets containing portions of the document, disk blocks, memory pages, etc. For each segment, a processor operating within an XML accelerator initiates parsing by identifying to a hardware parsing unit the document segment, a symbol table for the document and a location for storing state information regarding the parsing. Each segment is parsed in sequence, and the state information of the parsing is stored after each segment is completed, for retrieval when the next segment is to be parsed.

Claims

1. A method of virtualized parsing of an XML (Extensible Markup Language) document, the method comprising:

identifying multiple segments of the document;

identifying a symbol table for facilitating parsing of the document;

identifying a location for storing state information regarding the parsing;

for each of the multiple segments, configuring a corresponding work queue entry describing the segment; and

at a hardware parsing unit;

reading a work queue entry;

reading the stored state information unless the corresponding segment is an initial segment of the document; and

parsing the corresponding segment to extract document data and identify document structure.

2. The method of claim 1, further comprising, at the hardware parsing unit:

after said parsing, saving updated state information reflecting said parsing, unless the corresponding segment is a final segment of the document.

3. The method of claim 1, wherein after parsing a first segment of the document and before parsing a subsequent segment of the document, the hardware parsing unit parses a segment of a different document.

4. The method of claim 1, wherein said identifying comprises:

receiving multiple packets comprising portions of the document.

5. The method of claim 1, further comprising:

preloading the symbol table.

6. A computer readable medium storing instructions that, when executed by a computer, cause the computer to perform a method of virtualized parsing of an XML (Extensible Markup Language) document, the method comprising:

identifying multiple segments of the document;

identifying a symbol table for facilitating parsing of the document;

identifying a location for storing state information regarding the parsing;

for each of the multiple segments, configuring a corresponding work queue entry describing the segment; and

at a hardware parsing unit;

reading a work queue entry;

reading the stored state information unless the corresponding segment is an initial segment of the document; and

parsing the corresponding segment to extract document data and identify document structure.

7. A method of virtually parsing an XML (Extensible Markup Language) document, the method comprising:

identifying multiple segments within the document, including an initial segment and a final segment; and

for each segment;

if the segment is not the initial segment, loading state information saved in connection with the parsing of a previous segment;

parsing the segment; and

if the segment is not the final segment, saving state information reflecting the parsing of the segment.

8. The method of claim 7, wherein the parsing of each segment except the initial segment is initiated some period of time after completion of parsing of the previous segment.

9. The method of claim 7, wherein:

the document is received via a network interface; and

each segment corresponds to a separate packet comprising a portion of the document.

10. The method of claim 7, further comprising:

preloading a symbol table for use during parsing of each segment.

11. The method of claim 7, wherein said identifying comprises dividing the document into multiple segments.

12. The method of claim 7, further comprising, for each segment:

configuring an entry in a parsing work queue, said entry comprising;

a location of the segment in memory;

a length of the segment;

a location of a symbol table for storing symbols identified in the document; and

a length of the symbol table.

13. The method of claim 12, wherein the entry further comprises:

a location for storing the state information.

14. The method of claim 7, wherein:

said parsing is performed in a hardware module configured to interleave parsing of the document segments with segments of another document.

15. A hardware module for facilitating virtualized parsing of an XML (Extensible Markup Language) document, the hardware module comprising:

a hardware parsing unit configured to parse multiple segments of the document;

a symbol table memory configured to store a symbol table for storing symbols identified in the document during parsing of the segments;

a document memory configured to store the segments; and

a processor configured to invoke the parsing unit to parse the segments.

16. The hardware module of claim 15, further comprising:

a DMA (Direct Memory Access) engine configured to move the segments into the document memory.

17. The hardware module of claim 15, further comprising:

a cryptographic engine configured to apply a security scheme for the document.

18. The hardware module of claim 15, wherein the hardware parsing unit is configured to interleave parsing of the multiple segments with segments of one or more other documents.

19. The hardware module of claim 15, wherein the processor is configured to configure a work queue entry for each segment, the work queue entry comprising:

a location of the segment;

a length of the segment;

a location of the symbol table; and

a length of the symbol table.

20. The hardware module of claim 19, wherein each work queue entry further comprises:

a location for storing state information reflecting the parsing of the segments.

21. The hardware module of claim 20, wherein the hardware parsing unit is configured to service the work queue by:

reading a work queue entry corresponding to a document segment;

reading the state information;

parsing the segment; and

saving updated state information reflecting the parsing.

22. The hardware module of claim 21, wherein the hardware parsing unit:

reads the state information unless the segment is the initial segment of the document; and

saves the updated state information unless the segment is the final segment of the document.