I am parsing JSON to present a report. While parsing the field rating it can have either 3 which parses to JSONValue.integer or 3.4 which parses to JSONValue.floating and I need to convert them as float in the report. I have profiled the code to look for optimisation and the get_number function that converts the given input to floating point is taking a lot of time and also uses exceptions for the code.
I can use fast.d (https://github.com/mleise/fast) but I am trying to see if there are anymore optimisations that can be done on get_number function that is taking up time . Is there a way to get the floating point value without using the exceptions and are there any more optimisations that can be done?
redbus.d
import std.net.curl;
import std.exception;
import std.json;
import std.stdio;
import std.file;
import std.algorithm;
import std.array;
import std.conv;
import std.string;
auto fmt = "%35s | %10s | %10s | %10s | %15s";
auto value_fmt = "%35s | %10.2f | %10.0f | %10.2f | %15s";
void print_header() {
writeln("-----------------------------------------------------------------------------------------------");
writefln(fmt, "Name", "Price", "Window", "Rating", "Type");
writeln("-----------------------------------------------------------------------------------------------");
}
float get_number(T)(T item) {
float output = 0;
try {
output = to!float(item.integer);
} catch(Exception e) {
output = to!float(item.floating);
}
return to!float(output);
}
void print_item(T)(T item) {
writefln(value_fmt, item["Tvs"].str, item["MinFare"].get_number(), item["WnSt"].get_number(), item["Rtg"]["totRt"].get_number(), item["BusCategory"]["IsSleeper"]);
}
void main() {
auto content = readText("sample.json");
auto parsed = parseJSON(content);
auto raw = parsed["SRD"][0]["RIN"][0]["InvList"].array;
auto filtered = raw.filter!(item => to!bool(to!string(item["BusCategory"]["IsAc"])));
print_header();
foreach(item; filtered) {
print_item(item);
}
}
App specific trace log when ran with dmd -g -run redbus.d | grep redbus
======== Timer Is 3579545 Ticks/Sec, Times are in Microsecs ========
Num Tree Func Per
Calls Time Time Call
180 8673696 8300660 46114 @safe immutable(char)[] redbus.get_number!(std.json.JSONValue).get_number(std.json.JSONValue)
60 9448603 75423 1257 @safe void redbus.print_item!(std.json.JSONValue).print_item(std.json.JSONValue)
60 17581 10002 166 pure @safe void std.algorithm.iteration.__T12FilterResultS246redbus4mainFZ9__lambda1TAS3std4json9JSONValueZ.FilterResult.popFront()
2 110576 6987 3493 void redbus.print_header()
122 5635 5441 44 pure nothrow @property @nogc @safe bool std.algorithm.iteration.__T12FilterResultS246redbus4mainFZ9__lambda1TAS3std4json9JSONValueZ.FilterResult.empty()
60 4002 2877 47 pure nothrow ref @property @nogc @safe std.json.JSONValue std.algorithm.iteration.__T12FilterResultS246redbus4mainFZ9__lambda1TAS3std4json9JSONValueZ.FilterResult.front()
60 690 690 11 pure @safe bool redbus.main().__lambda1!(std.json.JSONValue).__lambda1(std.json.JSONValue)
2 386 348 174 pure ref @safe std.algorithm.iteration.__T12FilterResultS246redbus4mainFZ9__lambda1TAS3std4json9JSONValueZ.FilterResult std.algorithm.iteration.__T12FilterResultS246redbus4mainFZ9__lambda1TAS3std4json9JSONValueZ.FilterResult.__ctor(std.json.JSONValue[])
2 480 94 47 pure @safe std.algorithm.iteration.__T12FilterResultS246redbus4mainFZ9__lambda1TAS3std4json9JSONValueZ.FilterResult std.algorithm.iteration.__T6filterS246redbus4mainFZ9__lambda1Z.filter!(std.json.JSONValue[]).filter(std.json.JSONValue[])
2 28 28 14 pure nothrow @nogc @safe std.algorithm.iteration.__T12FilterResultS246redbus4mainFZ9__lambda1TAS3std4json9JSONValueZ.FilterResult std.algorithm.iteration.__T12FilterResultS246redbus4mainFZ9__lambda1TAS3std4json9JSONValueZ.FilterResult.opSlice()
Full trace log when ran with dmd -g -run redbus.d
======== Timer Is 3579545 Ticks/Sec, Times are in Microsecs ========
Num Tree Func Per
Calls Time Time Call
180 8673696 8300660 46114 @safe immutable(char)[] redbus.get_number!(std.json.JSONValue).get_number(std.json.JSONValue)
378142 7487455 5101529 13 pure @safe dchar std.json.parseJSON!(immutable(char)[]).parseJSON(immutable(char)[], int, std.json.JSONOptions).popChar()
403760 11591911 4118861 10 pure @safe dchar std.json.parseJSON!(immutable(char)[]).parseJSON(immutable(char)[], int, std.json.JSONOptions).peekChar()
13218 11298746 3847457 291 @safe immutable(char)[] std.json.parseJSON!(immutable(char)[]).parseJSON(immutable(char)[], int, std.json.JSONOptions).parseString()
2 3416630 3410981 1705490 @safe void[] std.file.read!(immutable(char)[]).read(immutable(char)[], ulong)
11694 26577653 2975245 254 @safe void std.json.parseJSON!(immutable(char)[]).parseJSON(immutable(char)[], int, std.json.JSONOptions).parseValue(ref std.json.JSONValue)
2 3189533 2760109 1380054 pure @safe void std.utf.validate!(immutable(char)[]).validate(const(immutable(char)[]))
50558 9391716 2176452 43 pure @safe void std.json.parseJSON!(immutable(char)[]).parseJSON(immutable(char)[], int, std.json.JSONOptions).skipWhitespace()
378142 2199763 1819030 4 pure @property @safe dchar std.range.primitives.front!(immutable(char)).front(immutable(char)[])
120448 4223189 1521014 12 pure @safe void std.array.Appender!(immutable(char)[]).Appender.put!(dchar).put(dchar)
121018 1447202 1447202 11 _D3std5array17__T8AppenderTAyaZ8Appender11__T3putTAaZ3putMFAaZ10bigDataFunMFNaNbNemZAa
121018 2663475 1216273 10 pure nothrow @safe void std.array.Appender!(immutable(char)[]).Appender.put!(char[]).put(char[])
378144 429423 429423 1 pure @trusted dchar std.utf.decode!(0, const(immutable(char)[])).decode(ref const(immutable(char)[]), ref ulong)
378142 380732 380732 1 pure @trusted dchar std.utf.decode!(0, immutable(char)[]).decode(ref immutable(char)[], ref ulong)
3844 1585268 379140 98 _D3std4json18__T9parseJSONTAyaZ9parseJSONFAyaiE3std4json11JSONOptionsZ10parseValueMFKS3std4json9JSONValueZ11readIntegerMFNaNfZv
17692 3044067 299545 16 pure @safe bool std.json.parseJSON!(immutable(char)[]).parseJSON(immutable(char)[], int, std.json.JSONOptions).testChar!(true, true).testChar(char)
3694 302920 283609 76 pure @safe ulong std.conv.parse!(ulong, immutable(char)[]).parse(ref immutable(char)[])
21172 5305573 253537 11 pure @safe void std.json.parseJSON!(immutable(char)[]).parseJSON(immutable(char)[], int, std.json.JSONOptions).checkChar!(true, true).checkChar(char)
2858 241132 241132 84 _D3std5stdio4File17LockingTextWriter10__T3putTaZ3putMFNfaZ12trustedFPUTCFNbNiNeiPS4core4stdc5stdio7__sFILEZi
749606 194721 194721 0 pure nothrow @property @nogc @safe bool std.range.primitives.empty!(char).empty(const(char[]))
180 146178 146178 812 nothrow @nogc @trusted int std.format.formatValue!(std.array.Appender!(immutable(char)[]).Appender, float, char).formatValue(std.array.Appender!(immutable(char)[]).Appender, float, ref std.format.FormatSpec!(char).FormatSpec).__lambda6()
168966 289542 140496 0 pure @safe dchar std.json.parseJSON!(immutable(char)[]).parseJSON(immutable(char)[], int, std.json.JSONOptions).getChar!(false).getChar()
372 175283 138897 373 @safe bool std.format.FormatSpec!(char).FormatSpec.writeUpToNextSpec!(std.stdio.File.LockingTextWriter).writeUpToNextSpec(std.stdio.File.LockingTextWriter)
378142 127665 127665 0 pure nothrow @nogc @trusted void std.range.primitives.popFront!(immutable(char)).popFront(ref immutable(char)[])
120838 88309 88309 0 pure @safe ulong std.utf.encode!(0).encode(ref char[4], dchar)
7004 269543 79286 11 pure @safe void std.json.parseJSON!(immutable(char)[]).parseJSON(immutable(char)[], int, std.json.JSONOptions).checkChar!(false, false).checkChar(char)
60 9448603 75423 1257 @safe void redbus.print_item!(std.json.JSONValue).print_item(std.json.JSONValue)
180 357433 73536 408 @safe immutable(char)[] std.conv.toStr!(immutable(char)[], float).toStr(float)
11694 1701071 65993 5 pure @safe dchar std.json.parseJSON!(immutable(char)[]).parseJSON(immutable(char)[], int, std.json.JSONOptions).getChar!(true).getChar()
62 546598 58901 950 @safe uint std.format.formattedWrite!(std.stdio.File.LockingTextWriter, char, immutable(char)[], immutable(char)[], immutable(char)[], immutable(char)[], immutable(char)[]).formattedWrite(std.stdio.File.LockingTextWriter, const(char[]), immutable(char)[], immutable(char)[], immutable(char)[], immutable(char)[], immutable(char)[])
624 57414 57414 92 nothrow @nogc @trusted ulong std.stdio.trustedFwrite!(char).trustedFwrite(shared(core.stdc.stdio.__sFILE)*, const(char[]))
310 287767 55386 178 @safe void std.format.formatRange!(std.stdio.File.LockingTextWriter, immutable(char)[], char).formatRange(ref std.stdio.File.LockingTextWriter, ref immutable(char)[], ref std.format.FormatSpec!(char).FormatSpec)
180 283897 51186 284 @safe void std.format.formatValue!(std.array.Appender!(immutable(char)[]).Appender, float, char).formatValue(std.array.Appender!(immutable(char)[]).Appender, float, ref std.format.FormatSpec!(char).FormatSpec)
2792 188331 44715 16 @safe void std.range.primitives.put!(std.stdio.File.LockingTextWriter, char).put(ref std.stdio.File.LockingTextWriter, char)
3786 51453 42260 11 pure @safe bool std.json.parseJSON!(immutable(char)[]).parseJSON(immutable(char)[], int, std.json.JSONOptions).testChar!(false, false).testChar(char)
1 42812121 40946 40946 _Dmain
2792 143615 40695 14 @safe void std.range.primitives.doPut!(std.stdio.File.LockingTextWriter, char).doPut(ref std.stdio.File.LockingTextWriter, ref char)
2858 276528 35396 12 @safe void std.stdio.File.LockingTextWriter.put!(char).put(char)
62 730778 28544 460 @safe void std.stdio.File.writefln!(char, immutable(char)[], immutable(char)[], immutable(char)[], immutable(char)[], immutable(char)[]).writefln(const(char[]), immutable(char)[], immutable(char)[], immutable(char)[], immutable(char)[], immutable(char)[])
58 27284 25878 446 pure @safe double std.conv.parse!(double, immutable(char)[]).parse(ref immutable(char)[])
4 61182 22565 5641 @safe void std.stdio.writeln!(immutable(char)[]).writeln(immutable(char)[])
668 36701 22086 33 pure nothrow @safe void std.array.Appender!(immutable(char)[]).Appender.put!(char).put(char)
10790 15562 15562 1 pure nothrow @nogc @safe dchar std.ascii.toLower!(dchar).toLower(dchar)
180 14091 14091 78 pure nothrow @nogc @trusted immutable(char)[] std.algorithm.searching.find!("a == b", immutable(char)[], char).find(immutable(char)[], char).trustedMemchr(ref immutable(char)[], ref char)
668 14165 12798 19 pure nothrow @nogc @safe void std.conv.emplaceRef!(char, char, char).emplaceRef(ref char, ref char)
310 307336 11476 37 void std.format.formatGeneric!(std.stdio.File.LockingTextWriter, immutable(char)[], char).formatGeneric(std.stdio.File.LockingTextWriter, const(void)*, ref std.format.FormatSpec!(char).FormatSpec)
62 741889 11111 179 @safe void std.stdio.writefln!(immutable(char)[], immutable(char)[], immutable(char)[], immutable(char)[], immutable(char)[], immutable(char)[]).writefln(immutable(char)[], immutable(char)[], immutable(char)[], immutable(char)[], immutable(char)[], immutable(char)[])
60 17581 10002 166 pure @safe void std.algorithm.iteration.__T12FilterResultS246redbus4mainFZ9__lambda1TAS3std4json9JSONValueZ.FilterResult.popFront()
314 51833 9902 31 @safe void std.stdio.File.LockingTextWriter.put!(immutable(char)[]).put(immutable(char)[])
310 30175 9395 30 @safe void std.range.primitives.doPut!(std.stdio.File.LockingTextWriter, const(char)[]).doPut(ref std.stdio.File.LockingTextWriter, ref const(char)[])
310 40073 8883 28 @safe void std.range.primitives.doPut!(std.stdio.File.LockingTextWriter, immutable(char)[]).doPut(ref std.stdio.File.LockingTextWriter, ref immutable(char)[])
180 23372 8492 47 pure @safe immutable(char)[] std.algorithm.searching.find!("a == b", immutable(char)[], char).find(immutable(char)[], char)
310 295860 8093 26 @safe void std.format.formatValue!(std.stdio.File.LockingTextWriter, immutable(char)[], char).formatValue(std.stdio.File.LockingTextWriter, immutable(char)[], ref std.format.FormatSpec!(char).FormatSpec)
16860 7657 7657 0 pure nothrow @nogc @safe void std.range.primitives.popFront!(immutable(ubyte)).popFront(ref immutable(ubyte)[])
180 9026 7524 41 pure nothrow @nogc @safe bool std.functional.safeOp!("<").safeOp!(immutable(int), ulong).safeOp(ref immutable(int), ref ulong)
2 110576 6987 3493 void redbus.print_header()
17034 6217 6217 0 pure nothrow ref @property @nogc @safe immutable(ubyte) std.range.primitives.front!(immutable(ubyte)).front(immutable(ubyte)[])
120 5515 5515 45 pure nothrow ref @property @nogc @safe std.json.JSONValue std.range.primitives.front!(std.json.JSONValue).front(std.json.JSONValue[])
122 5635 5441 44 pure nothrow @property @nogc @safe bool std.algorithm.iteration.__T12FilterResultS246redbus4mainFZ9__lambda1TAS3std4json9JSONValueZ.FilterResult.empty()
310 20779 5296 17 @safe void std.stdio.File.LockingTextWriter.put!(const(char)[]).put(const(char)[])
310 34821 4646 14 @safe void std.range.primitives.put!(std.stdio.File.LockingTextWriter, const(char)[]).put(ref std.stdio.File.LockingTextWriter, const(char)[])
180 13549 4523 25 pure nothrow @nogc @safe immutable(int) std.algorithm.comparison.min!(immutable(int), ulong).min(immutable(int), ulong)
2 5331 4353 2176 nothrow @nogc @safe std.internal.cstring.tempCString!(char, immutable(char)[]).tempCString(immutable(char)[]).Res std.internal.cstring.tempCString!(char, immutable(char)[]).tempCString(immutable(char)[])
180 365563 4136 22 @safe immutable(char)[] std.conv.to!(immutable(char)[]).to!(float).to(float)
130 4682 4089 31 pure nothrow @nogc @safe float std.conv.to!(float).to!(long).to(long)
180 361427 3994 22 @safe immutable(char)[] std.conv.toImpl!(immutable(char)[], float).toImpl(float)
310 44049 3975 12 @safe void std.range.primitives.put!(std.stdio.File.LockingTextWriter, immutable(char)[]).put(ref std.stdio.File.LockingTextWriter, immutable(char)[])
3786 3530 3530 0 pure nothrow @nogc @safe immutable(char)[] std.string.assumeUTF!(immutable(ubyte)).assumeUTF(immutable(ubyte)[])
34 3566 3268 96 pure @safe long std.conv.parse!(long, immutable(char)[]).parse(ref immutable(char)[])
60 4002 2877 47 pure nothrow ref @property @nogc @safe std.json.JSONValue std.algorithm.iteration.__T12FilterResultS246redbus4mainFZ9__lambda1TAS3std4json9JSONValueZ.FilterResult.front()
3786 2775 2775 0 pure nothrow @nogc @safe immutable(ubyte)[] std.string.representation!(immutable(char)).representation(immutable(char)[])
50 2790 2342 46 pure nothrow @nogc @safe float std.conv.to!(float).to!(double).to(double)
180 1501 1501 8 pure nothrow @nogc @safe bool std.functional.safeOp!("<").unsafeOp!(immutable(int), ulong).unsafeOp(immutable(int), ulong)
184 940 940 5 pure nothrow @property @nogc @safe bool std.range.primitives.empty!(std.json.JSONValue).empty(const(std.json.JSONValue[]))
60 919 919 15 pure nothrow @nogc @safe void std.range.primitives.popFront!(std.json.JSONValue).popFront(ref std.json.JSONValue[])
58 833 833 14 pure nothrow @nogc @safe ubyte std.ascii.toUpper!(immutable(ubyte)).toUpper(immutable(ubyte))
2 6607022 831 415 @safe immutable(char)[] std.file.readText!(immutable(char)[], immutable(char)[]).readText(immutable(char)[])
180 787 787 4 pure nothrow @nogc @safe bool std.utf.canSearchInCodeUnits!(char).canSearchInCodeUnits(dchar)
62 779 779 12 pure nothrow @nogc @trusted pure nothrow @safe void function(std.stdio.File.LockingTextWriter, const(void)*, ref std.format.FormatSpec!(char).FormatSpec)* std.format.formattedWrite!(std.stdio.File.LockingTextWriter, char, immutable(char)[], immutable(char)[], immutable(char)[], immutable(char)[], immutable(char)[]).formattedWrite(std.stdio.File.LockingTextWriter, const(char[]), immutable(char)[], immutable(char)[], immutable(char)[], immutable(char)[], immutable(char)[]).__lambda9()
60 690 690 11 pure @safe bool redbus.main().__lambda1!(std.json.JSONValue).__lambda1(std.json.JSONValue)
62 668 668 10 pure nothrow @nogc @trusted const(void*) std.format.formattedWrite!(std.stdio.File.LockingTextWriter, char, immutable(char)[], immutable(char)[], immutable(char)[], immutable(char)[], immutable(char)[]).formattedWrite(std.stdio.File.LockingTextWriter, const(char[]), immutable(char)[], immutable(char)[], immutable(char)[], immutable(char)[], immutable(char)[]).__lambda14!(immutable(char)[]).__lambda14(return ref immutable(char)[])
130 593 593 4 pure nothrow @nogc @safe float std.conv.toImpl!(float, long).toImpl(long)
62 574 574 9 pure nothrow @nogc @trusted const(void*) std.format.formattedWrite!(std.stdio.File.LockingTextWriter, char, immutable(char)[], immutable(char)[], immutable(char)[], immutable(char)[], immutable(char)[]).formattedWrite(std.stdio.File.LockingTextWriter, const(char[]), immutable(char)[], immutable(char)[], immutable(char)[], immutable(char)[], immutable(char)[]).__lambda16!(immutable(char)[]).__lambda16(return ref immutable(char)[])
668 517 517 0 pure nothrow @nogc @trusted void std.conv.emplaceInitializer!(std.conv.emplaceRef!(char, char, char).emplaceRef(ref char, ref char).S).emplaceInitializer(ref std.conv.emplaceRef!(char, char, char).emplaceRef(ref char, ref char).S)
62 494 494 7 pure nothrow @nogc @trusted pure nothrow @safe void function(std.stdio.File.LockingTextWriter, const(void)*, ref std.format.FormatSpec!(char).FormatSpec)* std.format.formattedWrite!(std.stdio.File.LockingTextWriter, char, immutable(char)[], immutable(char)[], immutable(char)[], immutable(char)[], immutable(char)[]).formattedWrite(std.stdio.File.LockingTextWriter, const(char[]), immutable(char)[], immutable(char)[], immutable(char)[], immutable(char)[], immutable(char)[]).__lambda15()
62 494 494 7 pure nothrow @nogc @trusted pure nothrow @safe void function(std.stdio.File.LockingTextWriter, const(void)*, ref std.format.FormatSpec!(char).FormatSpec)* std.format.formattedWrite!(std.stdio.File.LockingTextWriter, char, immutable(char)[], immutable(char)[], immutable(char)[], immutable(char)[], immutable(char)[]).formattedWrite(std.stdio.File.LockingTextWriter, const(char[]), immutable(char)[], immutable(char)[], immutable(char)[], immutable(char)[], immutable(char)[]).__lambda17()
668 479 479 0 pure nothrow @nogc @trusted std.conv.emplaceRef!(char, char, char).emplaceRef(ref char, ref char).S* std.conv.emplaceRef!(char, char, char).emplaceRef(ref char, ref char).__lambda5()
668 449 449 0 _D3std5array17__T8AppenderTAyaZ8Appender10__T3putTaZ3putMFaZ9__lambda2MFNaNbNiNeZAa
50 447 447 8 pure nothrow @nogc @safe float std.conv.toImpl!(float, double).toImpl(double)
2 26578112 437 218 @safe std.json.JSONValue std.json.parseJSON!(immutable(char)[]).parseJSON(immutable(char)[], int, std.json.JSONOptions)
62 423 423 6 pure nothrow @nogc @trusted const(void*) std.format.formattedWrite!(std.stdio.File.LockingTextWriter, char, immutable(char)[], immutable(char)[], immutable(char)[], immutable(char)[], immutable(char)[]).formattedWrite(std.stdio.File.LockingTextWriter, const(char[]), immutable(char)[], immutable(char)[], immutable(char)[], immutable(char)[], immutable(char)[]).__lambda18!(immutable(char)[]).__lambda18(return ref immutable(char)[])
62 422 422 6 pure nothrow @nogc @trusted const(void*) std.format.formattedWrite!(std.stdio.File.LockingTextWriter, char, immutable(char)[], immutable(char)[], immutable(char)[], immutable(char)[], immutable(char)[]).formattedWrite(std.stdio.File.LockingTextWriter, const(char[]), immutable(char)[], immutable(char)[], immutable(char)[], immutable(char)[], immutable(char)[]).__lambda10!(immutable(char)[]).__lambda10(return ref immutable(char)[])
62 416 416 6 pure nothrow @nogc @trusted pure nothrow @safe void function(std.stdio.File.LockingTextWriter, const(void)*, ref std.format.FormatSpec!(char).FormatSpec)* std.format.formattedWrite!(std.stdio.File.LockingTextWriter, char, immutable(char)[], immutable(char)[], immutable(char)[], immutable(char)[], immutable(char)[]).formattedWrite(std.stdio.File.LockingTextWriter, const(char[]), immutable(char)[], immutable(char)[], immutable(char)[], immutable(char)[], immutable(char)[]).__lambda11()
62 416 416 6 pure nothrow @nogc @trusted pure nothrow @safe void function(std.stdio.File.LockingTextWriter, const(void)*, ref std.format.FormatSpec!(char).FormatSpec)* std.format.formattedWrite!(std.stdio.File.LockingTextWriter, char, immutable(char)[], immutable(char)[], immutable(char)[], immutable(char)[], immutable(char)[]).formattedWrite(std.stdio.File.LockingTextWriter, const(char[]), immutable(char)[], immutable(char)[], immutable(char)[], immutable(char)[], immutable(char)[]).__lambda13()
62 385 385 6 pure nothrow @nogc @trusted const(void*) std.format.formattedWrite!(std.stdio.File.LockingTextWriter, char, immutable(char)[], immutable(char)[], immutable(char)[], immutable(char)[], immutable(char)[]).formattedWrite(std.stdio.File.LockingTextWriter, const(char[]), immutable(char)[], immutable(char)[], immutable(char)[], immutable(char)[], immutable(char)[]).__lambda12!(immutable(char)[]).__lambda12(return ref immutable(char)[])
668 370 370 0 pure nothrow ref @nogc @safe std.conv.emplaceRef!(char, char, char).emplaceRef(ref char, ref char).S std.conv.emplaceRef!(char, char, char).emplaceRef(ref char, ref char).S.__ctor(ref char)
2 386 348 174 pure ref @safe std.algorithm.iteration.__T12FilterResultS246redbus4mainFZ9__lambda1TAS3std4json9JSONValueZ.FilterResult std.algorithm.iteration.__T12FilterResultS246redbus4mainFZ9__lambda1TAS3std4json9JSONValueZ.FilterResult.__ctor(std.json.JSONValue[])
2 583 343 171 pure nothrow @nogc @safe std.utf.byCodeUnit!(const(char)[]).byCodeUnit(const(char)[]).ByCodeUnitImpl std.utf.byUTF!(char).byUTF!(const(char)[]).byUTF(const(char)[])
Adam's answer :
➜ D ldc2 -O3 -release redbus.d
➜ D time ./redbus > /dev/null
./redbus > /dev/null 0.01s user 0.00s system 80% cpu 0.021 total
➜ D time ./redbus > /dev/null
./redbus > /dev/null 0.01s user 0.00s system 81% cpu 0.021 total
➜ D time ./redbus > /dev/null
./redbus > /dev/null 0.01s user 0.00s system 82% cpu 0.023 total
➜ D time ./redbus > /dev/null
./redbus > /dev/null 0.01s user 0.00s system 81% cpu 0.021 total
➜ D perl -ne 'print if /========/...//' trace.log | grep get_number
120 2249 2249 18 float redbus.get_number(std.json.JSONValue)
Original run with exception :
➜ D time ./redbus > /dev/null
./redbus > /dev/null 0.01s user 0.01s system 40% cpu 0.039 total
➜ D time ./redbus > /dev/null
./redbus > /dev/null 0.01s user 0.00s system 80% cpu 0.023 total
➜ D time ./redbus > /dev/null
./redbus > /dev/null 0.01s user 0.00s system 64% cpu 0.023 total
➜ D perl -ne 'print if /========/...//' trace.log | grep get_number
120 4971306 4966534 41387 pure @safe float redbus.get_number!(std.json.JSONValue).get_number(std.json.JSONValue)
I betcha just changing your get_number to this will help improve the speed a lot:
float get_number(JSONValue item) {
float output = 0;
if(item.type == JSON_TYPE.FLOAT)
output = item.floating;
else if(item.type == JSON_TYPE.INTEGER)
output = item.integer;
return output;
}
Can you test it and let me know?
EDIT: in the comment, you asked about why the profile difference isn't quite reflected in the time difference. It is, though! This individual function is now 1,000x faster... but it was already reasonably fast to begin with so it is not a huge difference in the end.
Here's my comment explaining why you're expecting more than you should:
The timings given in the profile trace are microseconds, not milliseconds, there's a 1000x difference between them. The trace shows a time difference between my answer and the original code of about 40,000 microseconds... or 40 milliseconds, or 0.04 seconds. Considering that profiling itself adds a bit of overhead, you wouldn't see the full 0.04 second change in the final binary.... which matches up with your numbers well enough, on average my answer gave you a 0.02s boost (or 20,000 microseconds!), which is close to matching given profiling overhead being removed too.