Those value cache misses are not a problem. The value cache is a
per-query atomization cache, so it starts over on every query and misses
are to be expected.
Here is a query that doesn't touch the database at all, but the
query-meters output still shows the value cache in action.
let $a := <x id="1"/>
for $i in 1 to 10
return data($a/@id)
, xdmp:query-meters()
Change the '10' to 5, and watch the query-meters output.
-- Mike
On 2010-05-19 04:26, Vedavalli Radhika wrote:
> Thanks Geert,
> The suggestions helped us to fine-tune the query.
> Searching for chapter names is part of our requirement.
>
> Current query:
> for $a in cts:search(collection("collection_name"),
> cts:and-query((cts:element-attribute-range-query(xs:QName("book"),
> xs:QName("length"), ">=", 26),
> cts:element-attribute-range-query(xs:QName("book"), xs:QName("length"), "<=",
> 2620), cts:element-attribute-value-query(xs:QName("chapter"),
> xs:QName("name"), ('chap1','chap2','chap3','chap4')))), ("score-simple"))
>
> The query change has improved performance by considerable numbers.
> However running query-meter for the search query, gives back cache-misses for
> value cache.
> I am unable to understand where my query went wrong?
>
> The results are for a 10MB input file.
>
> Query-trace is also attached.
> We have defined two range element attribute indexes(for chapter,name and
> book,length) in the marklogic server.
>
> -<qm:query-meters xsi:schemaLocation="http://marklogic.com/xdmp/query-meters
> query-meters.xsd" xmlns:qm="http://marklogic.com/xdmp/query-meters";
> xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance";>
> <qm:elapsed-time>PT2.369S</qm:elapsed-time>
> <qm:requests>0</qm:requests>
> <qm:list-cache-hits>264098</qm:list-cache-hits>
> <qm:list-cache-misses>0</qm:list-cache-misses>
> <qm:in-memory-list-hits>0</qm:in-memory-list-hits>
> <qm:expanded-tree-cache-hits>1</qm:expanded-tree-cache-hits>
> <qm:expanded-tree-cache-misses>0</qm:expanded-tree-cache-misses>
> <qm:compressed-tree-cache-hits>0</qm:compressed-tree-cache-hits>
> <qm:compressed-tree-cache-misses>0</qm:compressed-tree-cache-misses>
> <qm:in-memory-compressed-tree-hits>0</qm:in-memory-compressed-tree-hits>
> <qm:value-cache-hits>1</qm:value-cache-hits>
> <qm:value-cache-misses>1</qm:value-cache-misses>
> <qm:regexp-cache-hits>0</qm:regexp-cache-hits>
> <qm:regexp-cache-misses>0</qm:regexp-cache-misses>
> <qm:link-cache-hits>0</qm:link-cache-hits>
> <qm:link-cache-misses>0</qm:link-cache-misses>
> <qm:filter-hits>1</qm:filter-hits>
> <qm:filter-misses>0</qm:filter-misses>
> <qm:fragments-added>0</qm:fragments-added>
> <qm:fragments-deleted>0</qm:fragments-deleted>
> <qm:fs-program-cache-hits>0</qm:fs-program-cache-hits>
> <qm:fs-program-cache-misses>0</qm:fs-program-cache-misses>
> <qm:db-program-cache-hits>0</qm:db-program-cache-hits>
> <qm:db-program-cache-misses>0</qm:db-program-cache-misses>
>
> <qm:fs-main-module-sequence-cache-hits>0</qm:fs-main-module-sequence-cache-hits>
>
> <qm:fs-main-module-sequence-cache-misses>0</qm:fs-main-module-sequence-cache-misses>
>
> <qm:db-main-module-sequence-cache-hits>0</qm:db-main-module-sequence-cache-hits>
>
> <qm:db-main-module-sequence-cache-misses>0</qm:db-main-module-sequence-cache-misses>
> <qm:fs-library-module-cache-hits>0</qm:fs-library-module-cache-hits>
> <qm:fs-library-module-cache-misses>0</qm:fs-library-module-cache-misses>
> <qm:db-library-module-cache-hits>0</qm:db-library-module-cache-hits>
> <qm:db-library-module-cache-misses>0</qm:db-library-module-cache-misses>
> -<qm:fragments>
> -<qm:fragment>
> <qm:root>book</qm:root>
> <qm:expanded-tree-cache-hits>1</qm:expanded-tree-cache-hits>
> <qm:expanded-tree-cache-misses>0</qm:expanded-tree-cache-misses>
> </qm:fragment>
> </qm:fragments>
> -<qm:documents>
> -<qm:document>
> <qm:uri>testbook</qm:uri>
> <qm:expanded-tree-cache-hits>1</qm:expanded-tree-cache-hits>
> <qm:expanded-tree-cache-misses>0</qm:expanded-tree-cache-misses>
> </qm:document>
> </qm:documents>
> </qm:query-meters>
>
> Results from query-trace
>
> 2010-05-19 12:54:37.876 Info: Http_Server: line 1:
> xdmp:eval("xdmp:query-trace(true()),
> cts:search(collection("collection_name&qu...", (),<options
> xmlns="xdmp:eval"><root>C:\Program
> Files\MarkLogic\Samples\cq</root><isolation>dif...</options>)
> 2010-05-19 12:54:37.876 Info: Http_Server: line 1: Analyzing path for search:
> fn:collection("collection_name")
> 2010-05-19 12:54:37.876 Info: Http_Server: line 1: Step 1 is searchable:
> fn:collection("collection_name")
> 2010-05-19 12:54:37.876 Info: Http_Server: line 1: Path is fully searchable.
> 2010-05-19 12:54:37.876 Info: Http_Server: line 1: Gathering constraints.
> 2010-05-19 12:54:37.876 Info: Http_Server: line 1: Step 1 contributed 1
> constraint: fn:collection("collection_name")
> 2010-05-19 12:54:39.431 Info: Http_Server: line 1: Comparison contributed int
> range value constraint: book/@length<mailto:book/@length> >= 48754
> 2010-05-19 12:54:39.431 Info: Http_Server: line 1: Comparison contributed int
> range value constraint: book/@length<mailto:book/@length> <= 487542500
> 2010-05-19 12:54:40.059 Info: Http_Server: line 1: Search query contributed 2
> constraints: cts:and-query((cts:element-attribute-range-query(fn:QName("",
> "book"), fn:QName("", "length"), ">=", 48754, (), 1),
> cts:element-attribute-range-query(fn:QName("", "book"), fn:QName("",
> "length"), "<=", 487542500, (), 1),
> cts:element-attribute-value-query(fn:QName("", "chapter"), fn:QName("",
> "name"), ("chap1", "chap2", "chap3", "chap4",....), ("lang=en"), 1)), ())
> 2010-05-19 12:55:24.935 Info: Http_Server: line 1: Executing search.
> 2010-05-19 12:55:25.240 Info: Http_Server: line 1: Selected 4 fragments to
> filter
>
> Thanks,
> Radhika
>
>
>
> Hi Radhika,
>
> Glancing through your query I notice some things. You have a nested
> and-query, do you know that cts:and-query can take an sequence of any length?
> And you have an or-query that tests the same element attribute value over and
> over again, with different values. It should be possible to pass one sequence
> with all allowed values to a single cts:element-attribute-value-query,
> eliminating the need for the or-query alltogether.
>
> Not sure why you are searching for specific chapter names though. Is that
> necessary?
>
> Kind regards,
> Geert
>
>>
>
> drs. G.P.H. (Geert) Josten
> Consultant
>
> Daidalos BV
> Hoekeindsehof 1-4
> 2665 JZ Bleiswijk
>
> T +31 (0)10 850 1200
> F +31 (0)10 850 1199
>
> mailto:geert.jos...@daidalos.nl
> http://www.daidalos.nl/
>
> KvK 27164984
>
> P Please consider the environment before printing this mail.
> De informatie - verzonden in of met dit e-mailbericht - is afkomstig van
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>
>> From:
>> general-boun...@developer.marklogic.com<mailto:general-boun...@developer.marklogic.com>
>> [mailto:general-boun...@developer.marklogic.com<mailto:general-boun...@developer.marklogic.com>]
>> On Behalf Of
>> Vedavalli Radhika
>> Sent: maandag 17 mei 2010 13:53
>> To: general@developer.marklogic.com<mailto:general@developer.marklogic.com>
>> Subject: [MarkLogic Dev General] Performance Tuning -
>> cts:search/cts:or Query
>>
>> We have a requirement for searching the marklogic database
>> for documents that satisfies a specific condition - length
>> attribute value should be within the specified range and one
>> or more chapters from the given chapters should be available.
>> The searched information is then filtered based on a fitness
>> calculation.
>> The execution of the query takes a long time if the dynamic
>> or-query becomes long (for bigger inputs, the or-query formed
>> will be longer) Are there better ways to optimize this search
>> query or atleast the or-query alone?
>>
>> QUERY:
>> for $a in
>> cts:search(collection(),
>> cts:and-query(
>> (
>> cts:and-query(
>> (cts:element-attribute-range-query(xs:QName("book"),
>> xs:QName("length"), ">=", 26),
>> cts:element-attribute-range-query(xs:QName("book"),
>> xs:QName("length"), "<=", 2620)) ), cts:or-query( (
>> cts:element-attribute-value-query(xs:QName("chapter"),
>> xs:QName("name"), "chap6"),
>> cts:element-attribute-value-query(xs:QName("chapter"),
>> xs:QName("name"), "newChap"),
>> cts:element-attribute-value-query(xs:QName("chapter"),
>> xs:QName("name"), "chap2"),
>> cts:element-attribute-value-query(xs:QName("chapter"),
>> xs:QName("name"), "chap5"),
>> cts:element-attribute-value-query(xs:QName("chapter"),
>> xs:QName("name"), "chap3"),
>> cts:element-attribute-value-query(xs:QName("chapter"),
>> xs:QName("name"), "chap9"),
>> cts:element-attribute-value-query(xs:QName("chapter"),
>> xs:QName("name"), "chap1"),
>> cts:element-attribute-value-query(xs:QName("chapter"),
>> xs:QName("name"), "chap4"))
>> )
>> )
>> ), ("score-simple"))
>> where $a[(cts:score($a))div(8*($a/book/@chapCnt<mailto:$a/book/@chapCnt>))
>> ge 0.1]
>> return element hit { attribute score { cts:score($a) }, $a }
>> SAMPLE DOCUMENT IN MARKLOGIC:
>> <book author="Author" length="262" id="unique-id" chapCnt="4">
>> <chapter pageStart="5" name="chap1" pageEnd="80" />
>> <chapter pageStart="83" name="chap2" pageEnd="180" />
>> <chapter pageStart="182" name="chap3" pageEnd="401" />
>> <chapter pageStart="405" name="chap4" pageEnd="567" />
>> </book>
>>
>> Thanks,
>> Radhika
>>
>>
>
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