performamce tuning

This commit is contained in:
Arndt 2016-09-04 19:28:15 +02:00
parent ead7f2ac6d
commit 51ff1b8482

View file

@ -2,28 +2,25 @@ package btools.util;
import java.util.ArrayList;
import java.util.List;
import java.util.Random;
/**
* Memory efficient Heap to get the lowest-key value
* of a set of key-object pairs
*
* Memory efficient Heap to get the lowest-key value of a set of key-object pairs
*
* @author ab
*/
public class SortedHeap<V>
public final class SortedHeap<V>
{
private int[][] al;
private int[] pa;
private int[] lp; // the low pointers
private Object[][] vla; // value list array
protected static final int MAXLISTS = 31; // enough for size Integer.MAX_VALUE
protected static final int MAXLISTS = 28; // enough for size = ca Integer.MAX_VALUE
private int size;
private boolean isClear = false;
public SortedHeap()
{
clear();
@ -34,230 +31,247 @@ public class SortedHeap<V>
*/
public V popLowestKeyValue()
{
int minId = 0;
int minIdx = -1;
for ( int i=1;; i++ )
int minId = 0;
int minIdx = -1;
for ( int i = 0;; i++ )
{
int[] ali = al[i];
if ( ali == null )
break;
int lpi = lp[i];
if ( lpi < 4 << i )
{
int[] ali = al[i];
if ( ali == null ) break;
int lpi = lp[i];
if ( lpi < ali.length )
int currentId = ali[lpi];
if ( minIdx < 0 || currentId < minId )
{
int currentId = ali[lpi];
if ( minIdx < 0 || currentId < minId )
{
minIdx = i;
minId = currentId;
}
minIdx = i;
minId = currentId;
}
}
if ( minIdx == -1 ) return null;
int lp_minIdx = lp[minIdx]++;
Object[] vla_minIdx = vla[minIdx];
V res =(V)vla_minIdx[lp_minIdx];
vla_minIdx[lp_minIdx] = null;
size--;
return res;
}
if ( minIdx == -1 )
return null;
int lp_minIdx = lp[minIdx]++;
Object[] vla_minIdx = vla[minIdx];
V res = (V) vla_minIdx[lp_minIdx];
vla_minIdx[lp_minIdx] = null;
size--;
return res;
}
/**
* add a key value pair to the heap
*
* @param id the key to insert
* @param value the value to insert object
*
* @param id
* the key to insert
* @param value
* the value to insert object
*/
public void add( int key, V value )
{
isClear = false;
size++;
// trivial shortcut if first array empty
if ( lp[1] == 1)
{
al[1][0] = key;
vla[1][0] = value;
lp[1] = 0;
return;
}
// trivial shortcut if second array empty
if ( lp[2] > 0 )
{
int[] al2 = al[2];
Object[] vla2 = vla[2];
int key1;
Object val1;
if ( lp[2] == 2 )
{
key1 = al[1][0];
val1 = vla[1][0];
lp[1] = 1;
}
else // == 1
{
key1 = al2[1];
val1 = vla2[1];
}
lp[2] = 0;
if ( key1 < key )
{
al2[0] = key1;
vla2[0] = val1;
al2[1] = key;
vla2[1] = value;
}
else
{
al2[1] = key1;
vla2[1] = val1;
al2[0] = key;
vla2[0] = value;
}
return;
}
// put the new entry in the first array
al[0][0] = key;
vla[0][0] = value;
pa[0] = 1;
pa[1] = 1;
pa[2] = 2;
// determine the first array big enough to take them all
int cnt = 4; // value count up to idx
int idx = 3;
int n = 4;
isClear = false;
size++;
if ( lp[0] == 0 )
{
sortUp();
}
int lp0 = lp[0];
int[] al0 = al[0];
Object[] vla0 = vla[0];
for(;;)
{
cnt += n-lp[idx];
if ( cnt <= n ) break;
pa[idx++] = n;
if ( lp0 == 4 || key < al0[lp0] )
{
al0[lp0-1] = key;
vla0[lp0-1] = value;
lp[0]--;
return;
}
al0[lp0-1] = al0[lp0];
vla0[lp0-1] = vla0[lp0];
lp0++;
}
}
private void sortUp()
{
// determine the first array big enough to take them all
int cnt = 4; // value count up to idx
int idx = 1;
int n = 8;
int firstNonEmptyIdx = 0;
int nonEmptyCount = 1;
for ( ;; )
{
int nentries = n - lp[idx];
if ( nentries > 0 )
{
cnt += n - lp[idx];
nonEmptyCount++;
}
if ( cnt <= n )
{
break;
}
idx++;
n <<= 1;
}
if ( idx == MAXLISTS )
{
throw new IllegalArgumentException( "overflow" );
}
// create it if not existant
if ( al[idx] == null )
{
al[idx] = new int[n];
vla[idx] = new Object[n];
}
int[] al_t = al[idx];
Object[] vla_t = vla[idx];
int lp_t = lp[idx];
// shift down content if any
if ( lp_t < n )
{
System.arraycopy(al_t, lp_t, al_t, 0, n-lp_t);
System.arraycopy(vla_t, lp_t, vla_t, 0, n-lp_t);
}
lp[idx] = 0;
pa[idx] = n - lp_t;
int tp = n-cnt; // target pointer
// now merge the contents of arrays 0...idx-1 into idx
while ( cnt > 0 )
// now merge the contents of arrays 0...idx into idx
while( nonEmptyCount > 1 )
{
int i=0;
while( pa[i] == lp[i] )
{
i++;
}
int maxId = al[i][pa[i]-1];
int maxIdx = i;
int i = firstNonEmptyIdx;
int minId = al[i][lp[i]];
int minIdx = i;
for ( i++; i<=idx; i++ )
for ( i++; i <= idx; i++ )
{
int p = pa[i];
if ( p > lp[i] )
if ( 4 << i > lp[i] )
{
int currentId = al[i][p-1];
if ( currentId > maxId )
int currentId = al[i][lp[i]];
if ( currentId < minId )
{
maxIdx = i;
maxId = currentId;
minIdx = i;
minId = currentId;
}
}
}
// current maximum found, copy to target array
--n;
al[idx][n] = maxId;
vla[idx][n] = vla[maxIdx][pa[maxIdx]-1];
--cnt;
--pa[maxIdx];
// current minimum found, copy to target array
int sp = lp[minIdx]; // source-pointer
al_t[tp] = minId;
vla_t[tp++] = vla[minIdx][sp];
if ( minIdx != idx )
{
vla[minIdx][sp] = null;
}
if ( ++lp[minIdx] == 4 << minIdx )
{
nonEmptyCount--;
if ( minIdx == firstNonEmptyIdx )
{
while( lp[firstNonEmptyIdx] == 4 << firstNonEmptyIdx )
{
firstNonEmptyIdx++;
}
}
}
}
lp[idx] = n;
while(--idx > 0) lp[idx] = al[idx].length;
// only one non-empty index left, so just copy the remaining entries
if ( firstNonEmptyIdx != idx ) // no self-copy needed
{
int[] al_s = al[firstNonEmptyIdx];
Object[] vla_s = vla[firstNonEmptyIdx];
int sp = lp[firstNonEmptyIdx]; // source-pointer
while( sp < 4 << firstNonEmptyIdx )
{
al_t[tp] = al_s[sp];
vla_t[tp++] = vla_s[sp];
vla_s[sp++] = null;
}
lp[firstNonEmptyIdx] = sp;
}
lp[idx] = n-cnt; // new target low pointer
}
public void clear()
{
if ( !isClear )
{
isClear = true;
size = 0;
// pointer array
pa = new int[MAXLISTS];
if ( !isClear )
{
isClear = true;
size = 0;
lp = new int[MAXLISTS];
lp = new int[MAXLISTS];
// allocate key lists
al = new int[MAXLISTS][];
al[0] = new int[1]; // make the first arrays
al[1] = new int[1];
al[2] = new int[2];
// allocate key lists
al = new int[MAXLISTS][];
al[0] = new int[4]; // make the first array
// same for the values
vla = new Object[MAXLISTS][];
vla[0] = new Object[1];
vla[1] = new Object[1];
vla[2] = new Object[2];
int n = 1;
lp[0] = 0;
for( int idx=1; idx < MAXLISTS; idx++ )
{
lp[idx] = n;
n <<= 1;
}
}
// same for the values
vla = new Object[MAXLISTS][];
vla[0] = new Object[4];
int n = 4;
for ( int idx = 0; idx < MAXLISTS; idx++ )
{
lp[idx] = n;
n <<= 1;
}
}
}
public List<V> getExtract()
{
int div = size / 1000 + 1;
ArrayList<V> res = new ArrayList<V>(size / div );
int cnt = 0;
for ( int i=1;; i++ )
int div = size / 1000 + 1;
ArrayList<V> res = new ArrayList<V>( size / div );
int cnt = 0;
for ( int i = 1;; i++ )
{
int[] ali = al[i];
if ( ali == null )
break;
int lpi = lp[i];
Object[] vlai = vla[i];
int n = 4 << i;
while (lpi < n)
{
int[] ali = al[i];
if ( ali == null ) break;
int lpi = lp[i];
Object[] vlai = vla[i];
int n = ali.length;
while ( lpi < n )
if ( ( ++cnt ) % div == 0 )
{
if ( (++cnt) % div == 0 )
{
res.add( (V)vla[i][lpi] );
}
lpi++;
res.add( (V) vla[i][lpi] );
}
lpi++;
}
return res;
}
return res;
}
public static void main(String[] args)
{
SortedHeap<String> sh = new SortedHeap<String>();
Random rnd = new Random();
for( int i = 0; i< 6; i++ )
{
int val = rnd.nextInt( 1000000 );
sh.add( val, "" + val );
val = rnd.nextInt( 1000000 );
sh.add( val, "" + val );
sh.popLowestKeyValue();
}
int cnt = 0;
int lastval = 0;
for(;;)
{
String s = sh.popLowestKeyValue();
if ( s == null ) break;
cnt ++;
int val = Integer.parseInt( s );
System.out.println( "popLowestKeyValue: " + val);
// Assert.assertTrue( "sorting test", val >= lastval );
lastval = val;
}
// Assert.assertTrue( "total count test", cnt == 100000 );
}
}