Browse Benchmarks
Benchmark ::EXISTENTIAL-ATTRIB : Existential branch, then attribute step
(submitted at 2006-06-26T18:00:00) |
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| Authors: |
Ioana Manolescu (Gemo Group, INRIA Futurs, France) Philippe Michiels (Universiteit Antwerpen, Belgium) Cédric Miachon (BD, LRI, Université Paris Sud 11, France) |
| Categories: |
XPath,Query Scalability
|
| Target: |
All systems |
| Engine type: |
persistent-storage main-memory streaming |
| Measure: |
The measure targets the total execution time of a simple XPath query consisting of an existential child navigation path, and a single attribute step starting from the document root node.
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Result unit: |
Milliseconds |
| Query: |
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The query used in this micro-benchmark checks for the existence of a chain of nodes under the root, and finally fetches one attribute of the root.
For every integer n, the corresponding query, named EXISTENTIAL-ATTRIB(n), is:
/t1[t2/.../tn]/@id
The purpose of this query is to test the performance of existential navigation (XPath branch tests). As n grows, the number of nodes reachable by t2/.../tn grows exponentially. However, given the squery brackets surrounding this branch, the evaluation of this query can be much faster than if all these nodes are actually enumerated. The attribute step is introduced to obtain a controlled (and small) returned result size.
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Syntax: |
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Language: |
XPath 1.0 |
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Generator: |
generateQ15.java |
| Document: |
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The document exponential2.xml is a tree such that:
- the root is labeled t1
- the root has 2 children, labeled t2
-
each t2 child of the root has two children, labeled t3...
More generally, all nodes but the leaves have two children, all nodes at level i are labeled ti, and the depth of the document is 19 (all nodes at depth 19 are leaves).
The document's size is about 11 MB.
The document is generated using the MemBeR document generator with the following configuration file:
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Generator: |
MemBeR.Generator |
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Configuration file: |
Q11_exp_MemBeR_Generator_config.xml |
| Parameters: |
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Parameter
n:
This is the number of consecutive child navigation steps in the query.
|
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This parameter characterizes the: |
query |
|
Unit: |
None. |
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Value Range: |
[
1
..
19
]
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Distribution: |
uniform |
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Scale: |
ordinal |
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Parameter
docsize:
This is the size of the document. |
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This parameter characterizes the: |
doc |
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Unit: |
Byte |
|
Values: |
11946474 |
|
Distribution: |
uniform |
|
Scale: |
ordinal |
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|
|
| Methodology: |
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Running scenario: queryScale
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Test the influence of the number of child steps on the total execution time. All other parameters are fixed.
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| Parameter instantiation: |
|
Name |
Value(s) |
|
n |
1
,
2
,
3
,
4
,
5
,
6
,
7
,
8
,
9
,
10
,
11
,
12
,
13
,
14
,
15
,
16
,
17
,
18
,
19 |
|
|