Config: increased default map key capacity from 2k to 2M - this improves...

Config: increased default map key capacity from 2k to 2M - this improves performance of group by queries

core/src/main/java/io/questdb/PropServerConfiguration.java

@@ -263,7 +263,7 @@ public class PropServerConfiguration implements ServerConfiguration {
         this.sqlFastMapLoadFactor = getDouble(properties, "cairo.fast.map.load.factor", 0.5);
         this.sqlJoinContextPoolCapacity = getInt(properties, "cairo.sql.join.context.pool.capacity", 64);
         this.sqlLexerPoolCapacity = getInt(properties, "cairo.lexer.pool.capacity", 2048);
-        this.sqlMapKeyCapacity = getInt(properties, "cairo.sql.map.key.capacity", 2048);
+        this.sqlMapKeyCapacity = getInt(properties, "cairo.sql.map.key.capacity", 2048 * 1024);
         this.sqlMapPageSize = getIntSize(properties, "cairo.sql.map.page.size", 4 * 1024 * 1024);
         this.sqlModelPoolCapacity = getInt(properties, "cairo.model.pool.capacity", 1024);
         this.sqlSortKeyPageSize = getIntSize(properties, "cairo.sql.sort.key.page.size", 4 * 1024 * 1024);

core/src/main/java/io/questdb/cairo/map/FastMap.java

@@ -146,6 +146,45 @@ public class FastMap implements Map {
         this.cursor = new FastMapCursor(record, this);
     }
 
+    private static boolean eqMixed(long a, long b, long lim) {
+        while (b < lim - 8) {
+            if (Unsafe.getUnsafe().getLong(a) != Unsafe.getUnsafe().getLong(b)) {
+                return false;
+            }
+            a += 8;
+            b += 8;
+        }
+
+        while (b < lim) {
+            if (Unsafe.getUnsafe().getByte(a++) != Unsafe.getUnsafe().getByte(b++)) {
+                return false;
+            }
+        }
+        return true;
+    }
+
+    private static boolean eqLong(long a, long b, long lim) {
+        while (b < lim) {
+            if (Unsafe.getUnsafe().getLong(a) != Unsafe.getUnsafe().getLong(b)) {
+                return false;
+            }
+            a += 8;
+            b += 8;
+        }
+        return true;
+    }
+
+    private static boolean eqInt(long a, long b, long lim) {
+        while (b < lim) {
+            if (Unsafe.getUnsafe().getInt(a) != Unsafe.getUnsafe().getInt(b)) {
+                return false;
+            }
+            a += 4;
+            b += 4;
+        }
+        return true;
+    }
+
     @Override
     public void clear() {
         kPos = kStart;
@@ -228,20 +267,16 @@ public class FastMap implements Map {
         a += keyDataOffset;
         b += keyDataOffset;
 
-        while (b < lim - 8) {
-            if (Unsafe.getUnsafe().getLong(a) != Unsafe.getUnsafe().getLong(b)) {
-                return false;
-            }
-            a += 8;
-            b += 8;
+        long d = lim - b;
+        if (d % Long.BYTES == 0) {
+            return eqLong(a, b, lim);
         }
 
-        while (b < lim) {
-            if (Unsafe.getUnsafe().getByte(a++) != Unsafe.getUnsafe().getByte(b++)) {
-                return false;
-            }
+        if (d % Integer.BYTES == 0) {
+            return eqInt(a, b, lim);
         }
-        return true;
+
+        return eqMixed(a, b, lim);
     }
 
     long getAppendOffset() {

core/src/main/java/io/questdb/std/Hash.java

@@ -23,8 +23,6 @@
 
 package io.questdb.std;
 
-import io.questdb.std.str.DirectBytes;
-
 public final class Hash {
     private Hash() {
     }
@@ -40,10 +38,6 @@ public final class Hash {
         return s == null ? -1 : (Chars.hashCode(s) & 0xFFFFFFF) & max;
     }
 
-    public static int boundedHash(DirectBytes s, int max) {
-        return s == null ? -1 : (Chars.hashCode(s) & 0xFFFFFFF) & max;
-    }
-
     /**
      * Calculates positive integer hash of memory pointer using Java hashcode() algorithm.
      *
@@ -53,7 +47,7 @@ public final class Hash {
      */
     public static int hashMem(long p, int len) {
         int hash = 0;
-        long hi = p + len;
+        final long hi = p + len;
         while (hi - p > 3) {
             hash = (hash << 5) - hash + Unsafe.getUnsafe().getInt(p);
             p += 4;

core/src/test/java/io/questdb/PropServerConfigurationTest.java

@@ -143,7 +143,7 @@ public class PropServerConfigurationTest {
         Assert.assertEquals(0.5, configuration.getCairoConfiguration().getSqlFastMapLoadFactor(), 0.0000001);
         Assert.assertEquals(64, configuration.getCairoConfiguration().getSqlJoinContextPoolCapacity());
         Assert.assertEquals(2048, configuration.getCairoConfiguration().getSqlLexerPoolCapacity());
-        Assert.assertEquals(2048, configuration.getCairoConfiguration().getSqlMapKeyCapacity());
+        Assert.assertEquals(2097152, configuration.getCairoConfiguration().getSqlMapKeyCapacity());
         Assert.assertEquals(4 * 1024 * 1024, configuration.getCairoConfiguration().getSqlMapPageSize());
         Assert.assertEquals(1024, configuration.getCairoConfiguration().getSqlModelPoolCapacity());
         Assert.assertEquals(4 * 1024 * 1024, configuration.getCairoConfiguration().getSqlSortKeyPageSize());