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yacy_search_server
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more performance hacks: 10% more speed for Base64.compare() which is really often used in YaCy code

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git-svn-id: https://svn.berlios.de/svnroot/repos/yacy/trunk@5846 6c8d7289-2bf4-0310-a012-ef5d649a1542
pull/1/head
orbiter 16 years ago
parent 8ffb9889e1
commit b53790abb1
2 changed files with 61 additions and 15 deletions
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13
source/de/anomic/kelondro/index/IndexTest.java
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@ -87,7 +87,7 @@ public class IndexTest {
long t3 = System.currentTimeMillis();
System.out.println("time for TreeMap<byte[]> test: " + (t3 - t2) + ", " + bugs + " bugs");
System.out.println("memory for TreeMap<byte[]>: " + (freeStartTree - freeEndTree) / mb + " MB\n");
// test hash map
Runtime.getRuntime().gc();
long freeStartHash = MemoryControl.available();
@ -122,7 +122,16 @@ public class IndexTest {
long t7 = System.currentTimeMillis();
System.out.println("time for kelondroMap<byte[]> test: " + (t7 - t6) + ", " + bugs + " bugs");
System.out.println("memory for kelondroMap<byte[]>: " + (freeStartKelondro - freeEndKelondro) / mb + " MB\n");
System.exit(0);
}
}
/*
time for TreeMap<byte[]> generation: 3117
time for TreeMap<byte[]> test: 3495, 0 bugs
memory for TreeMap<byte[]>: 29 MB
*/

63
source/de/anomic/kelondro/order/Base64Order.java
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@ -58,7 +58,7 @@ public class Base64Order extends AbstractOrder<byte[]> implements ByteOrder, Cod
private final boolean rfc1113compliant;
private final char[] alpha;
private final byte[] ahpla;
private final short[] ab; // decision table for comparisments
private final byte[] ab; // decision table for comparisments
public Base64Order(final boolean up, final boolean rfc1113compliant) {
// if we choose not to be rfc1113compliant,
@ -67,9 +67,10 @@ public class Base64Order extends AbstractOrder<byte[]> implements ByteOrder, Cod
this.asc = up;
alpha = (rfc1113compliant) ? alpha_standard : alpha_enhanced;
ahpla = (rfc1113compliant) ? ahpla_standard : ahpla_enhanced;
ab = new short[1 << 14];
ab = new byte[1 << 14];
byte acc, bcc;
short c;
byte c;
// pre-compute comparisment results: this omits one single ahpla lookup during comparisment
for (char ac: alpha) {
for (char bc: alpha) {
acc = ahpla[ac];
@ -415,15 +416,22 @@ public class Base64Order extends AbstractOrder<byte[]> implements ByteOrder, Cod
}
public final int compare(final byte[] a, final byte[] b) {
return (asc) ? compare0(a, 0, a.length, b, 0, b.length) : compare0(b, 0, b.length, a, 0, a.length);
return (asc) ?
((zero == null) ? compares(a, b) : compare0(a, 0, a.length, b, 0, b.length))
:
((zero == null) ? compares(b, a) : compare0(b, 0, b.length, a, 0, a.length));
}
public final int compare(final byte[] a, final int aoffset, final int alength, final byte[] b, final int boffset, final int blength) {
return (asc) ? compare0(a, aoffset, alength, b, boffset, blength) : compare0(b, boffset, blength, a, aoffset, alength);
return (asc) ?
compare0(a, aoffset, alength, b, boffset, blength)
:
compare0(b, boffset, blength, a, aoffset, alength);
}
public final int compare0(final byte[] a, final int aoffset, final int alength, final byte[] b, final int boffset, final int blength) {
private final int compare0(final byte[] a, final int aoffset, final int alength, final byte[] b, final int boffset, final int blength) {
if (zero == null) return compares(a, aoffset, alength, b, boffset, blength);
// we have an artificial start point. check all combinations
final int az = compares(a, aoffset, alength, zero, 0, Math.min(alength, zero.length)); // -1 if a < z; 0 if a == z; 1 if a > z
final int bz = compares(b, boffset, blength, zero, 0, Math.min(blength, zero.length)); // -1 if b < z; 0 if b == z; 1 if b > z
@ -431,14 +439,41 @@ public class Base64Order extends AbstractOrder<byte[]> implements ByteOrder, Cod
return sig(az - bz);
}
public final int compares(final byte[] a, final int aoffset, final int alength, final byte[] b, final int boffset, final int blength) {
private final int compares(final byte[] a, final byte[] b) {
assert (ahpla.length == 128);
short i = 0;
final int al = a.length;
final int bl = b.length;
final short ml = (short) Math.min(al, bl);
byte ac, bc;
while (i < ml) { // trace point
assert (i < a.length) : "i = " + i + ", aoffset = " + 0 + ", a.length = " + a.length + ", a = " + NaturalOrder.arrayList(a, 0, al);
assert (i < b.length) : "i = " + i + ", boffset = " + 0 + ", b.length = " + b.length + ", b = " + NaturalOrder.arrayList(b, 0, al);
ac = a[i];
assert (ac >= 0) && (ac < 128) : "ac = " + ac + ", a = " + NaturalOrder.arrayList(a, 0, al);
bc = b[i];
assert (bc >= 0) && (bc < 128) : "bc = " + bc + ", b = " + NaturalOrder.arrayList(b, 0, al);
assert ac != 0;
assert bc != 0;
//if ((ac == 0) && (bc == 0)) return 0; // zero-terminated length
if (ac != bc) return ab[(ac << 7) | bc];
i++;
}
// compare length
if (al > bl) return 1;
if (al < bl) return -1;
// they are equal
return 0;
}
private final int compares(final byte[] a, final int aoffset, final int alength, final byte[] b, final int boffset, final int blength) {
assert (aoffset + alength <= a.length) : "a.length = " + a.length + ", aoffset = " + aoffset + ", alength = " + alength;
assert (boffset + blength <= b.length) : "b.length = " + b.length + ", boffset = " + boffset + ", blength = " + blength;
assert (ahpla.length == 128);
int i = 0;
short i = 0;
final int al = Math.min(alength, a.length - aoffset);
final int bl = Math.min(blength, b.length - boffset);
final int ml = Math.min(al, bl);
final short ml = (short) Math.min(al, bl);
byte ac, bc;
//byte acc, bcc;
//int c = 0;
@ -448,12 +483,14 @@ public class Base64Order extends AbstractOrder<byte[]> implements ByteOrder, Cod
ac = a[aoffset + i];
assert (ac >= 0) && (ac < 128) : "ac = " + ac + ", a = " + NaturalOrder.arrayList(a, aoffset, al);
bc = b[boffset + i];
if ((ac == 0) && (bc == 0)) return 0; // zero-terminated length
assert (bc >= 0) && (bc < 128) : "bc = " + bc + ", b = " + NaturalOrder.arrayList(b, boffset, al);
assert ac != 0;
assert bc != 0;
//if ((ac == 0) && (bc == 0)) return 0; // zero-terminated length
if (ac == bc) {
// shortcut in case of equality: we don't need to lookup the ahpla value
i++;
continue;
// shortcut in case of equality: we don't need to lookup the ahpla value
i++;
continue;
}
//acc = ahpla[ac];
//assert (acc >= 0) : "acc = " + acc + ", a = " + NaturalOrder.arrayList(a, aoffset, al) + "/" + new String(a, aoffset, al) + ", aoffset = 0x" + Integer.toHexString(aoffset) + ", i = " + i + "\n" + NaturalOrder.table(a, 16, aoffset);

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