Changes

This [[Module Library|XQuery Module]] contains various testingfunctions to test and profile code, profiling and helper functionsto dump information to standard output.

All functions and errors in this module are assigned to the {{Code|http://basex.org/modules/prof}} namespace, which is statically bound to the {{Code|prof}} prefix.<br/>All errors are assigned to the <code><nowiki>http://basex.org/errorsmodules/prof</nowiki></code> namespace, which is statically bound to the {{Code|bxerrprof}} prefix.<br/>

=Performance Functions=

==prof:timetrack==

|{{Func|prof:timetrack|$expr expression as item()|item()*}}<br />{{Func|prof:timetrack|$expr expression as item(), $cache options as xs:boolean|itemmap()*}}<br />{{Func|prof:time|$expr as item(), $cache as xs:boolean, $label as xs:string?|item()*}}

|Measures the execution time needed to evaluate and memory consumption required for evaluating the specified {{Code|$exprexpression}} and sends it to standard error or, if returns a map with the GUI is used, to the Info Viewresults.<br />If The following {{Code|$cacheoptions}} are available:* {{Code|time}} is set to : Include execution time in result as {{Code|xs:decimal}} (unit: milliseconds; default: true).* {{Code|memory}}: Include memory consumption in result as {{Code|xs:integer}} (unit: bytes; default: false).* {{Code|value}}: Include value in result (default: true).Helpful notes:* If you are not interested in some of the returned results, you should disable them to save time and memory.* Profiling might change the result execution behavior of your code: An expression that might be executed iteratively will be temporarily cachedby the profiling function. This way* If a value has a compact internal representation, memory consumption will be very low, a potential iterative execution of even if the expression (which often yields different serialized result may consume much more memory.* Please note that memory usage) profiling is blockedonly approximative, so it can be quite misleading.<br/>A thirdIf the memory option is enabled, optional argument {{Code|$label}} may main-memory will be specified garbage-collected before and after evaluation to tag improve the profiling resultquality of the measurement.

* {{Code|profReturn a human-readable representation of the memory consumption caused by fetching an XML document (<code>fetch:xml</code> is used, as <code>fn:doc</code> may already be evaluated at compilation time():<syntaxhighlight lang="1 to 100000xquery">prof:track(fetch:xml('factbook.xml'))?memory=> prof:human()}} may output {{Code|25.69 ms}}.</syntaxhighlight>* {{Code|The function call <code>prof:timetrack(("1 to 100000"1000000)[. mod 2 = 0], truemap { 'time': false()})}} may output </code> will return something similar to:<syntaxhighlight lang="xquery">map {{Code|208 "memory": 21548400, "value": (2, 4, 6, 8, 10, ...12 ms)}}.</syntaxhighlight>

==prof:memtime==

|{{Func|prof:memtime|$expr as item()|item()*}}<br />{{Func|prof:memtime|$expr as item(), $cache as xs:boolean|item()*}}<br />{{Func|prof:mem|$expr as item(), $cache as xs:boolean, $label as xs:string|item()*}}

|Measures the memory allocated by evaluating time needed to evaluate {{Code|$expr}} and sends it outputs a string to standard error or, if the GUI is used, to the Info View.<br />If {{Code|$cache}} is set to {{Code|true()}}, the result will be temporarily cached. This way, a potential iterative execution of the expression (which often yields different memory usage) is blocked.<br/>A third, An optional argument {{Code|$label}} may be specified to tag the profiling result. See {{Function|Profiling|prof:track}} for further notes.

* {{Code|prof:mbtime("1 to 100000")}} may output {{Code|0 Bytes}}.* {{Code|prof:mb("1 to 100000", truesleep(1000))}} may output outputs something similar to {{Code|261000.678 mb99 ms}}.

==prof:sleepmemory==

|{{Func|prof:sleepmemory|$ms expr as xs:integeritem()|empty-sequenceitem()*}}<br />{{Func|prof:memory|$expr as item(), $label as xs:string|item()*}}

|Sleeps for Measures the memory allocated by evaluating {{Code|$expr}} and outputs a string to standard error or, if the GUI is used, to the Info View. An optional {{Code|$label}} may be specified number of millisecondsto tag the profiling result. See {{Function|Profiling|prof:track}} for further notes.

==prof:humancurrent-ms==

|{{Func|prof:humancurrent-ms||$number as xs:integer|xs:string}}<br />

|Returns a human-readable representation the number of milliseconds passed since 1970/01/01 UTC. The granularity of the specified value depends on the underlying operating system and may be larger. For example, many operating systems measure time in units of tens of milliseconds.|-| '''Properties'''|In contrast to {{Code|$numberfn:current-time()}}, the function is ''non-deterministic'' and returns different values every time it is called. Its evaluation order will be preserved by the compiler.

| '''ExampleExamples'''

* {{Code|convert:integer-to-dateTime(prof:humancurrent-ms(16384))}} returns the current miliseconds in the {{Code|16Kxs:dateTime}} format.|} ==prof:current-ns== {| width='100%'|-| width='120' | '''Signatures'''|{{Func|prof:current-ns||xs:integer}}<br />|-| '''Summary'''|Returns the current value of the most precise available system timer in nanoseconds.|-| '''Properties'''|In contrast to {{Code|fn:current-time()}}, the function is ''non-deterministic'' and returns different values every time it is called. Its evaluation order will be preserved by the compiler.|-| '''Examples'''| Measures the time of an expression:<syntaxhighlight lang="xquery">let $ns1 := prof:current-ns()return ( (: process to measure :) (1 to 1000000)[. = 0], let $ns2 := prof:current-ns() let $ms := ((($ns2 - $ns1) idiv 10000) div 100) return $ms || ' ms')</syntaxhighlight>

|{{Func|prof:dump|$expr as item()*|empty-sequence()}}<br />{{Func|prof:dump|$expr as item()*, $label as xs:string|empty-sequence()}}<br />

|Prints a list of all current local and global variable assignments to standard error or, if the GUI is used, to the Info View.<br />As every query is optimized before being evaluated, not all of the original variables may be visible in the output. Moreover, many variables of function calls will disappear because functions are inlined. Function inlining can be turned off by setting the [[Options#INLINELIMIT{{Option|INLINELIMIT]] option }} to <code>0</code>.

* {{Code|for $x in 1 to 2 return ($x, prof:variables())}} will dump the values of <code>$x</code> to standard error.

==prof:current-mstype==

|{{Func|prof:current-mstype|$expr as item()*|xs:integeritem()*}}<br />

|Returns the number of milliseconds passed since 1970/01/01 UTC. The granularity Similar to {{Code|fn:trace($expr, $msg)}}, but instead of a user-defined message, it emits the value depends on the underlying operating system compile-time type and may be larger. For example, many operating systems measure time in units estimated result size of tens of millisecondsits argument.|} ==prof:gc== {| width='100%'|-| width='120' | '''Signatures'''|{{Func|prof:gc||empty-sequence()}}<br/>{{Func|prof:gc|$count as xs:integer|empty-sequence()}}

| '''PropertiesSummary'''|In contrast to Enforces Java garbage collection. If no {{Code|fn:current-time()$count}}is supplied, the garbage will be collected once. Please note that this function is ''non-deterministic''should only be used for debugging purposes; in productive code, as it returns different values every time it is called. Its evaluation order will be preserved by best to trust the compilergarbage collecting strategies of Java.

==prof:current-nsruntime==

|{{Func|prof:current-nsruntime|$name of xs:string|xs:integer}}<br />

|Returns the current value of the most precise specified runtime {{Code|$option}}. The following options exist:* {{Code|max}}: Maximum memory that the Java virtual machine will attempt to use.* {{Code|total}}: Total memory in the Java virtual machine (varies over time).* {{Code|used}}: Currently used memory (varies over time, will shrink after garbage collection).* {{Code|processors}}: number of processors available system timer in nanosecondsto the Java virtual machine.|-|{{Code|option}}|The specified option is unknown.

| '''PropertiesExamples'''|In contrast to {{Code|fn* <code>prof:current-timegc(3)}}, the function is prof:human(prof:runtime('used'non-deterministic'', as it ))</code> performs some garbage collection and returns different values every time it is called. Its evaluation order will be preserved by the compilercurrently used amount of memory in a user-friendly format.

* Added: <code>[[#prof:variables|prof:variables]]</code>

* Added: <code>[[#prof:void|prof:void]]</code>

* Added: <code>[[#prof:human|prof:human]]</code>

* Added: <code>[[#prof:dump|prof:dump]]</code>, <code>[[#prof:current-ms|prof:current-ms]]</code>, <code>[[#prof:current-ns|prof:current-ns]]</code>