Performance - Threads - Sys Resources = What's the CPU Speed n RAM ?

Question

Hi all,
I am writing a small program based on quick port scanning (pure Java). For that purpose I'm using threads to make the connections. I am using multiple threads in parallel. While running 64 threads theres a 10% CPU usage whereas on 128 threads theres a 60% usage (On AMD 500 Mhz).
Now obviously I dont want anybody with a 233 Mhz running my program with 128 threads and surely not the one with 1 Ghz being limited to only 128 threads. Thats why I need to find out the clients resources like CPU speed, total RAM etc. How do I do that ?
Someone suggested using JNDI for windows registry. I'm not sure how to do it that way. (if anyone can provide me a little code?) Is there another way round to this problem?
Any help appreciated.

Answer 1

My friend
please try to understand the problem here is not of OPTIMIZATION OF THREAD SERVICES but the OPTIMAL NUMBER OF THREADS TO BE USED at certain processor speeds.
fine I agree about different performances of processors (pentium 1Ghz != AMD 1Ghz)
but surely (pentium 1Ghz ~ AMD 1Ghz ~ other 1Ghz).
and anyway in my program I'm taking the performance margins by 200Mhz to be on the safer side
i.e.
x1-x2 no of threads for say 300-500Mhz,
y1-y2 no of threads for 500-700Mhz,
z1-z2 no of threads for 700-1Ghz. Get the point.?
Heres an incomplete example of my prog (if now anyone can make out a fair idea of the problem) :
import java.net.*;
import java.io.*;
class QuickPortScan
public static void main(String args[])
long tstart,tend;
ScanThread scant=null;
String name=null,ok=null;
/* int tnum; This is the number of threads I want to calculate */
System.out.println(" Quick Port Scanner BLAH BLAH BLAH!");
System.out.print("-------------------BLAH BLAH BLAH!--------------\nEnter 'y' To Proceed: ");
try{
ok = new BufferedReader(new
InputStreamReader(System.in)).readLine();
if(ok.equals("Y")||ok.equals("y")){}
else{ System.exit(0); }
     System.out.print("Enter The HOSTNAME: ");
     name = new BufferedReader(new
     InputStreamReader(System.in)).readLine();} catch(IOException e){}
     System.out.println("Scanning 65,535 Ports, Please Be Patient...\n");
/* Now I would like to get the CPU speed here somehow
and then calculate tnum and pass it as param below */
tstart = System.currentTimeMillis();
for(int i=1;i<=tnum;i++)
     scant = new ScanThread(name,i /* ,tnum */);
     scant.start();
try{ scant.join(); }
catch(InterruptedException ine){ System.out.println("Main Thread Interrupted!"); }
     tend = System.currentTimeMillis();
     double ttaken = (tend-tstart)/1000;
     if(ttaken>59)
     System.out.println("Total Time Taken For Scan: "+(ttaken/60)+" minutes.");
     else System.out.println("Total Time Taken For Scan: "+ttaken+" seconds.");
} //END QuickPortScan class
class ScanThread extends Thread
String name;
int port,tno;
/* int nloop; This is the number of sleep-break loops calculated according to number of threads */
Socket sock;
static boolean scanFirst = true;
boolean breakOut = false,breakIn = false;
public ScanThread(String nm,int i /* ,int j */)
     name = nm;
     port = i;
     tno = i;
/* nloop = (j * whatever + whenever - together); */
public void run()
     for(int round1=1;round1<=32 /*nloop otherwise*/;round1++)
     if(breakOut==true){ break; }
     for(int round2=1;round2<=32;round2++)
try{ 
/* SOCKET
CONNECTION
IMPLEMENTATION */
     }     try{sleep(75);}catch(InterruptedException ie){}
public synchronized void portInc(int open)
     if(open==1){System.out.println("Port "+port+" Vulnerable!, Scanning...");}
     if(port==16384){System.out.println("25% Completed, Scanning Further...");}
     else if(port==32768){System.out.println("50% Completed, Scanning Further...");}
     else if(port==49152){System.out.println("75% Completed, Scanning Further...");}
     port = port + nt; // nt is the NUMBER OF THREADS
     if(port>=65536){if(scanFirst==true){System.out.println("*****SCAN COMPLETE!*****");
     scanFirst=false;} breakOut=true; breakIn=true;}
} // END ScanThread class