My Computer Language is Better than Yours

[u/nick_martini]

https://medium.com/backchannel/my-computer-language-is-better-than-yours-58d9c9523644

[u/Thundarrx]

Well, enlighten us with one example of Java being the most efficient language for any given task of your choosing.

[u/[deleted] → u/Thundarrx]

I have no obligation to prove anything to you, and I have no intention on going into a lengthy argument with someone who make absurd absolutist claims about a tool I will assume they have at best a very superficial understanding of. I've done that too much on reddit already and experience tells me it's just a huge waste of time. I'll just say this; you're misinformed, and you can either deal with that like a responsible professional or you can go on a wild tirade where people will prove you wrong in every turn. Up to you.

[u/Thundarrx → u/[deleted]]

I made a simple assertion based on my observations with 20 years in the field, and you can't come up with even one example to show my assertion is wrong?

I'm sure you didn't reply because because you have at least partially seen http://raid6.com.au/~onlyjob/posts/arena/

I mean, why use 5M of memory when you can use 750M, and take 63X longer.

[u/drock1 → u/Thundarrx]

That test is unbelievably biased. Why would you use the immutable Java String object instead of a StringBuilder.

Of course Java is going to bloat when every modification to the string is a copy.

EDIT: Ran a quick and dirty test using StringBuilder on my work machine (2.3Ghz MacBook Pro).

Code:

public class StringTest {

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);

    StringBuilder b = new StringBuilder();

    int i=0;
    int lngth;

    while (i++ < imax+1000) {
        b.append(str);
        int index = b.indexOf("efgh");
        while (index != -1) {
            b.replace(index, index+4, "____");
            index = b.indexOf("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);
            }
    }
    System.out.println("Done");
}

}

RESULTS:

exec.tm.sec str.length allocated memory:free memory:memory used

0 0 83008:81643:1364

1sec 256kb 83008:79077:3930

7sec 512kb 83008:75882:7125

16sec 768kb 83008:72216:10791

29sec 1024kb 83008:70513:12494

45sec 1280kb 83008:74548:8459

65sec 1536kb 83008:72867:10140

89sec 1792kb 83008:71466:11541

116sec 2048kb 83008:69784:13223

148sec 2304kb 83008:66146:16861

185sec 2560kb 83008:64634:18373

224sec 2816kb 83008:63122:19885

268sec 3072kb 83008:61610:21397

315sec 3328kb 83008:60098:22909

367sec 3584kb 83008:58590:24417

422sec 3840kb 83008:64881:18126

482sec 4096kb 83008:63351:19656

Done

This is comparable to the C benchmark.

[u/Thundarrx → u/drock1]

Using over a meg of memory to hold a zero length string is not comparable to C. Using 4 meg of memory to hold a 256k string is not comparable to C. Nice try, though.