How would you optimize this?
Materialize the sequence and index it?
Or evaluate multiple expressions on the sequence during one scan?
Or ...?
Till
On Jan 5, 2010, at 12:55 AM, Till Westmann wrote:
> Hmm, is this test part of a later revision of the test suite?
> For me test execution never was a real problem ...
>
> How slow is it?
>
> Thanks,
> Till
>
> On Jan 4, 2010, at 9:50 PM, Vinayak Borkar wrote:
>
>> Its not an infinite loop --
>> Expressions/Construct/DirectConElem/DirectConElemContent//Constr-cont-document-3.xq
>>
>> is taking a long time to run. I am pasting the query below.
>>
>> The query iterates over about 1.1 M integers 70 at a time and calls
>> subsequence() for the 70 items in the window. This is a quadratic operation
>> in the engine -- and takes a long time.
>>
>> Should we optimize this case?
>>
>>
>> Thanks,
>> Vinayak
>>
>>
>> --- Query begin ---
>>
>>
>> declare variable $codepoints as xs:integer+ := (9, (: 0x9 :)
>> 10,(: 0xA :)
>> 13,(: 0xD :)
>> 32 to 55295, (: 0x20 - 0xD7FF
>> :)
>> 57344 to 65532, (: 0xE000 -
>> 0xFFFD :)
>> 65536 to 1114111 (: 0x10000 -
>> 0x10FFFF :));
>> declare variable $count as xs:integer := count($codepoints);
>> declare variable $lineWidth as xs:integer := 70;
>>
>> <allCodepoints>
>> <!-- Each <r>-element represents a codepoint range. The 's' attribute
>> is the start codepoint, the 'e' attribute is the end codepoint.
>> Note that these are only *Hints*, since the character range is not
>> contiguous.
>> -->
>> {
>> "
",
>> "
",
>> (: The outputted file is rather big, so to make it managable, we output
>> a chunk of $lineWidth characters in each element.
>> :)
>> for $i in (1 to $count idiv $lineWidth)
>> let $startOffset := (($i - 1) * $lineWidth) + 1
>> return (<r s="{$codepoints[$startOffset]}"
>> e="{$codepoints[$startOffset] + $lineWidth}">
>> {
>> codepoints-to-string(subsequence($codepoints,
>> $startOffset, $lineWidth))
>> }
>> </r>, "
")
>> }
>> </allCodepoints>
>>
>> --- Query end ---
>>
>> Vinayak Borkar wrote:
>>> Till,
>>> Does XTest on the test suite terminate? Some query is throwing the engine
>>> into an infinite loop. Do you see this?
>>> Thanks,
>>> Vinayak
