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wyk86485481
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Java, Python, Ruby, PHP, C 等语言性能对比

  •  
  •   wyk86485481 · 2016-08-19 12:59:40 +08:00 · 2072 次点击
    这是一个创建于 2861 天前的主题,其中的信息可能已经有所发展或是发生改变。
    **代码功能:**循环拼接字符串,并替换子字符串

    **硬件环境:**Intel Core2 Duo [email protected] CPU; 2 GB RAM; OS Debian GNU/Linux 2.6.32 i686

    ### 代码执行时长
    ![代码运行时长]( https://static.oschina.net/uploads/img/201511/14142908_AExs.png)

    **代码性能对比图**
    ![代码性能对比图]( https://static.oschina.net/uploads/img/201511/14144357_WZxg.png)

    最慢: Java gcj (native executable)
    较慢: Java (openJDK); Java (Sun); Lua
    稍慢: tcl; Javascript (spiderm onkey)
    较快: Python; Ruby; PHP; C++; Javascript V8; C; Perl5
    最快的是 Perl ,最慢的 gcj ,你能接受吗?

    ### 内存使用情况
    ![内存使用情况]( https://static.oschina.net/uploads/img/201511/14143131_XRkd.png)

    **内存对比图:**
    ![内存对比图]( https://static.oschina.net/uploads/img/201511/14150514_3YBp.png)

    ### 测试源码:

    C (source); Result: C gcc (Debian 4.4.4-1) 4.4.4

    ~~~.c
    #include <stdio.h>
    #include <stdlib.h>
    #include <string.h>
    #include <time.h>

    int main(){

    setbuf(stdout,NULL); //disable output buffering

    char *str=malloc(8);
    strcpy(str,"abcdefgh");

    str=realloc(str,strlen(str)+8);
    strcat(str,"efghefgh"); //sprintf(str,"%s%s",str,"efghefgh");

    int imax=1024/strlen(str)*1024*4;

    printf("%s","exec.tm.sec\tstr.length\n"); //fflush(stdout);

    time_t starttime=time(NULL);
    char *gstr=malloc(0);
    int i=0;
    char *pos;
    int lngth;

    char *pos_c=gstr;
    int str_len=strlen(str);

    while(i++ < imax+1000){
    lngth=strlen(str)*i;
    gstr=realloc(gstr,lngth+str_len);
    strcat(gstr,str); //sprintf(gstr,"%s%s",gstr,str);
    pos_c+=str_len;

    pos=gstr;
    while(pos=strstr(pos,"efgh")){
    memcpy(pos,"____",4);
    }

    if(lngth % (1024*256)==0){
    printf("%dsec\t\t%dkb\n",time(NULL)-starttime,lngth/1024); //fflush(stdout);
    }
    }
    //printf("%s\n",gstr);

    }
    ~~~

    C++ (source) Result: C++ g++ (Debian 4.4.3-7) 4.4.3

    ~~~.cpp
    #include <iostream>
    #include <string>
    #include <time.h>

    using namespace std;

    main ()
    {
    string str = "abcdefgh";
    str += "efghefgh";
    int imax = 1024 /str.length() * 1024 *4;
    time_t currentTime = time(NULL);
    cout << "exec.tm.sec\tstr.length" << endl;

    string find= "efgh";
    string replace ="____";
    string gstr;
    int i=0;
    int length;
    // int end=0; // size_t end=0;

    while(i++ < imax +1000){
    gstr += str;
    gstr = gstr;
    size_t start, sizeSearch=find.size(), end=0;

    while((start=gstr.find(find,end))!=string::npos){
    end=start+sizeSearch;
    gstr.replace(start,sizeSearch,replace);
    }
    length = str.length()*i;
    if((length%(1024 * 256))==0){
    cout << time(NULL) - currentTime << "sec\t\t" << length/1024 << "kb" << endl;
    }
    }
    // cout << gstr << endl;

    return 0;
    }
    ~~~

    Javascript (source); Results: Javascript (Spiderm onkey - Mozilla) 1.8.0 pre-release 1 2007-10-03,
    Javascript (V8 - Chrome)

    ~~~.javascript
    #!/usr/local/bin/js

    var str = "abcdefgh"+"efghefgh";
    var imax = 1024 / str.length * 1024 * 4;

    var time = new Date();
    print("exec.tm.sec\tstr.length");

    var gstr = "";
    var i=0;
    var lngth;

    while (i++ < imax+1000) {
    gstr += str;
    gstr = gstr.replace(/efgh/g, "____");
    lngth=str.length*i;
    if ((lngth % (1024*256)) == 0) {
    var curdate=new Date();
    print(parseInt(((curdate.getTime()-time.getTime())/1000))+"sec\t\t"+lngth/1024+"kb");
    }
    }
    ~~~

    Java (source) Results: Java (OpenJDK) "1.6.0 18",
    Java (Sun) "1.6.0 16",
    Java (gcj) (Debian 4.4.3-1) 4.4.3

    ~~~.java
    public class java_test {

    public static final void main(String[] args) throws Exception {
    String str = "abcdefgh"+"efghefgh";
    int imax = 1024 / str.length() * 1024 * 4;

    long time = System.currentTimeMillis();
    System.out.println("exec.tm.sec\tstr.length\tallocated memory:free memory:memory used");
    Runtime runtime = Runtime.getRuntime();
    System.out.println("0\t\t0\t\t"+runtime.totalMemory()/1024 +":"+ runtime.freeMemory()/1024+":"+(runtime.totalMemory()-runtime.freeMemory())/1024);

    String gstr = "";
    int i=0;
    int lngth;

    while (i++ < imax+1000) {
    gstr += str;
    gstr = gstr.replaceAll("efgh", "____");
    lngth=str.length()*i;
    if ((lngth % (1024*256)) == 0) {
    System.out.println(((System.currentTimeMillis()-time)/1000)+"sec\t\t"+lngth/1024+"kb\t\t"+runtime.totalMemory()/1024+":"+runtime.freeMemory()/1024+":"+(runtime.totalMemory()-runtime.freeMemory())/1024);
    }
    }
    }
    }
    ~~~

    Perl5 (source); Result: This is perl, v5.10.1

    ~~~.perl
    #!/usr/bin/perl
    $|=1; #disable output buffering, this is necessary for proper output through pipe

    my $str='abcdefgh'.'efghefgh';
    my $imax=1024/length($str)*1024*4; # 4mb

    my $starttime=time();
    print "exec.tm.sec\tstr.length\n";

    my $gstr='';
    my $i=0;

    while($i++ < $imax+1000){ #adding 1000 iterations to delay exit. This will allow to capture memory usage on last step

    $gstr.=$str;
    $gstr=~s/efgh/____/g;
    my $lngth=length($str)*$i; ## my $lngth=length($gstr); # Perhaps that would be a slower way
    print time()-$starttime,"sec\t\t",$lngth/1024,"kb\n" unless $lngth % (1024*256); #print out every 256kb
    }
    ~~~

    PHP (source); Result: PHP 5.3.1-5 with Suhosin-Patch (cgi-fcgi)

    ~~~.php
    <?php


    $str="abcdefgh"."efghefgh";
    $imax=1024/strlen($str)*1024*4; # 4mb

    $starttime=time();
    print("exec.tm.sec\tstr.length\n");

    $gstr='';
    $i=0;

    while($i++ < $imax+1000){

    $gstr.=$str;
    $gstr=preg_replace('/efgh/','____',$gstr);
    $lngth=strlen($str)*$i;
    if($lngth % (1024*256)==0){
    print (time()-$starttime."sec\t\t".($lngth/1024)."kb\n");
    }
    }

    ?>
    ~~~

    Python3 (source); Result: Python 3.1.3

    ~~~.python
    #!/usr/bin/python3 -u
    import re
    import time
    import sys

    str='abcdefgh'+'efghefgh'
    imax=1024/len(str)*1024*4 # 4mb

    starttime=time.time();
    print "exec.tm.sec\tstr.length"
    sys.stdout.flush()

    gstr=''
    i=0

    while (i < imax+1000):
    i=i+1
    gstr+=str
    gstr=re.sub('efgh','____',gstr)
    lngth=len(str)*i
    if(lngth % (1024*256) == 0):
    print int(time.time()-starttime),"sec\t\t",(lngth/1024),"kb"
    sys.stdout.flush()
    ~~~

    Ruby (source); Result: ruby 1.8.7

    ~~~.ruby
    #!/usr/bin/ruby
    $stdout.sync=true;

    str='abcdefgh'+'efghefgh';
    imax=1024/str.length*1024*4; # 4mb

    starttime=Time.new;
    print("exec.tm.sec\tstr.length\n");

    gstr='';
    i=0;

    while i < imax+1000
    i=i+1;
    gstr+=str;
    gstr=gstr.gsub(/efgh/, "____")

    lngth=str.length*i;
    if(lngth % (1024*256)==0)
    print(((Time.new-starttime).ceil).to_s+"sec\t\t",(lngth/1024).to_s,"kb\n");
    end
    end

    #puts gstr;
    ~~~

    Lua (source); Result: Lua 5.1.4

    ~~~.lua
    #!/usr/bin/lua

    io.stdout:setvbuf "no"; -- io.flush();

    str='abcdefgh'..'efghefgh';
    imax=1024/string.len(str)*1024*4; -- 4mb

    starttime=os.time();
    print "exec.tm.sec\tstr.length";

    gstr='';
    i=0;

    while i < imax+1000 do
    i=i+1;
    gstr=gstr..str;
    gstr=string.gsub(gstr,"efgh","____");
    lngth=string.len(str)*i;
    if(math.mod(lngth,1024*256)==0) then
    print(os.time()-starttime.."sec\t\t"..(lngth/1024).."kb");
    end
    end
    ~~~

    tcl (source); Result: tcl 8.4.19

    ~~~.tcl
    #!/usr/bin/tclsh

    set str "abcdefgh"
    append str "efghefgh"

    set imax [expr {1024/[string length $str]*1024*4}]

    set starttime [clock clicks -milliseconds]
    puts "exec.tm.sec\tstr.length";

    set gstr ""
    set i 0

    while {$i<[expr {$imax+1000}]} {
    incr i
    append gstr $str;
    regsub -all {efgh} $gstr ____ gstr
    set lngth [expr {[string length $str]*$i}]
    if {[expr {$lngth % (1024*256)}] == 0} {
    puts "[expr int([expr [clock clicks -milliseconds] - $starttime] / 1000)]sec\t\t[expr {$lngth/1024}]kb"
    }
    }

    exit
    ~~~

    ### 结论

    各语言随着版本升级,也在不断优化,想要用好每个语言的特性,需要摸透她的脾气,这个需要不断的加深了解。

    选语言就像选恋人,情人眼里出西施,你中意的,就是最好的,所以对以上结果别太较真。

    转自: http://www.yinqisen.cn/blog-685.html
    EXE
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    EXE  
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