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Optimize RowIDCoercer
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@sdruzkin @elharo
sdruzkin authored and elharo committed May 22, 2024
1 parent 5f64ec8 commit a629a91
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Showing 2 changed files with 49 additions and 41 deletions.
57 changes: 33 additions & 24 deletions presto-hive/src/main/java/com/facebook/presto/hive/RowIDCoercer.java
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Expand Up @@ -16,29 +16,40 @@
import com.facebook.presto.common.Subfield;
import com.facebook.presto.common.block.Block;
import com.facebook.presto.common.block.BlockBuilder;
import com.facebook.presto.common.block.LazyBlock;
import com.facebook.presto.common.predicate.TupleDomainFilter;
import com.facebook.presto.common.type.BigintType;
import com.facebook.presto.common.type.Type;
import com.facebook.presto.common.type.VarbinaryType;
import io.airlift.slice.Slice;
import io.airlift.slice.Slices;

import java.nio.ByteBuffer;
import java.nio.ByteOrder;
import java.nio.charset.StandardCharsets;

import static com.facebook.presto.common.type.BigintType.BIGINT;
import static com.facebook.presto.common.type.VarbinaryType.VARBINARY;
import static com.google.common.base.Preconditions.checkArgument;
import static java.nio.charset.StandardCharsets.UTF_8;
import static java.util.Objects.requireNonNull;

public class RowIDCoercer
implements HiveCoercer
{
private final byte[] rowIDPartitionComponent;
private final byte[] rowGroupID; // file name
// These two fields are mutated. This class is not thread-safe.
private final ByteBuffer rowIDBytes;
private final Slice rowIDSlice;

public RowIDCoercer(byte[] rowIDPartitionComponent, String rowGroupID)
public RowIDCoercer(byte[] partitionComponent, String rowGroupID)
{
this.rowIDPartitionComponent = requireNonNull(rowIDPartitionComponent);
this.rowGroupID = rowGroupID.getBytes(StandardCharsets.UTF_8);
requireNonNull(partitionComponent, "partitionComponent is null");
requireNonNull(rowGroupID, "rowGroupID is null");

// precompute content of the row_id slice
byte[] rowGroupIdComponent = rowGroupID.getBytes(UTF_8);
byte[] bytes = new byte[Long.BYTES + rowGroupIdComponent.length + partitionComponent.length];
this.rowIDBytes = ByteBuffer.wrap(bytes).order(ByteOrder.LITTLE_ENDIAN);
this.rowIDSlice = Slices.wrappedBuffer(bytes);
this.rowIDSlice.setBytes(Long.BYTES, rowGroupIdComponent);
this.rowIDSlice.setBytes(Long.BYTES + rowGroupIdComponent.length, partitionComponent);
}

@Override
Expand All @@ -51,26 +62,24 @@ public TupleDomainFilter toCoercingFilter(TupleDomainFilter filter, Subfield sub
@Override
public Type getToType()
{
return VarbinaryType.VARBINARY;
return VARBINARY;
}

@Override
public Block apply(Block in)
public Block apply(Block rowNumberBlock)
{
BlockBuilder out = VarbinaryType.VARBINARY.createBlockBuilder(null, in.getPositionCount());
for (int i = 0; i < in.getPositionCount(); i++) {
if (in.isNull(i)) {
out.appendNull();
continue;
requireNonNull(rowNumberBlock, "rowNumberBlock is null");

int positionCount = rowNumberBlock.getPositionCount();
Block lazyBlock = new LazyBlock(positionCount, (block) -> {
BlockBuilder blockBuilder = VARBINARY.createBlockBuilder(null, positionCount, rowIDSlice.length());
for (int i = 0; i < positionCount; i++) {
long rowNumber = BIGINT.getLong(rowNumberBlock, i);
rowIDBytes.putLong(0, rowNumber);
VARBINARY.writeSlice(blockBuilder, rowIDSlice);
}
long rowNumber = BigintType.BIGINT.getLong(in, i);
ByteBuffer rowID = ByteBuffer.allocateDirect(this.rowIDPartitionComponent.length + this.rowGroupID.length + 8).order(ByteOrder.LITTLE_ENDIAN);
rowID.putLong(rowNumber);
rowID.put(this.rowGroupID);
rowID.put(this.rowIDPartitionComponent);
rowID.flip();
VarbinaryType.VARBINARY.writeSlice(out, Slices.wrappedBuffer(rowID));
}
return out.build();
block.setBlock(blockBuilder.build());
});
return lazyBlock;
}
}
33 changes: 16 additions & 17 deletions presto-hive/src/test/java/com/facebook/presto/hive/TestRowIDCoercer.java
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Expand Up @@ -17,17 +17,21 @@
import com.facebook.presto.common.block.Block;
import com.facebook.presto.common.block.LongArrayBlockBuilder;
import com.facebook.presto.common.type.VarbinaryType;
import com.google.common.primitives.Longs;
import org.testng.annotations.Test;

import java.nio.ByteBuffer;
import java.nio.ByteOrder;
import java.util.Arrays;

import static java.nio.charset.StandardCharsets.UTF_8;
import static org.testng.Assert.assertEquals;

public class TestRowIDCoercer
{
private final byte[] rowIdPartitionComponent = {(byte) 8, (byte) 9};
private HiveCoercer coercer = new RowIDCoercer(rowIdPartitionComponent, "some_filename.dat");
private static final String ROW_GROUP_ID = "some_filename.dat";
private static final byte[] ROW_GROUP_ID_BYTES = ROW_GROUP_ID.getBytes(UTF_8);
private static final byte[] PARTITION_COMPONENT = {(byte) 8, (byte) 9};
private HiveCoercer coercer = new RowIDCoercer(PARTITION_COMPONENT, ROW_GROUP_ID);

@Test
public void testGetToType()
Expand Down Expand Up @@ -56,23 +60,18 @@ public void testApply()
assertRowId(rowIDs, 5, Long.MAX_VALUE);
}

private static void assertRowId(Block rowIDs, int position, long expected)
private static void assertRowId(Block rowIDs, int position, long rowNumber)
{
byte[] rowID = rowIDs.getSlice(position, 0, rowIDs.getSliceLength(position)).getBytes();
assertEquals(rowID.length, 27);
assertEquals(rowID[25], (byte) 8);
assertEquals(rowID[26], (byte) 9);
byte[] rowNumber = reverse(Arrays.copyOf(rowID, 8));
assertEquals(Longs.fromByteArray(rowNumber), expected);
}

// I'm sure this can be micro-optimized. It's only a test. Clarity matters more.
private static byte[] reverse(byte[] in)
{
byte[] out = new byte[in.length];
for (int i = 0; i < in.length; i++) {
out[i] = in[in.length - i - 1];
}
return out;
byte[] actualPartitionComponent = Arrays.copyOfRange(rowID, 25, 27);
assertEquals(actualPartitionComponent, PARTITION_COMPONENT);

byte[] actualRowGroupId = Arrays.copyOfRange(rowID, 8, 25);
assertEquals(actualRowGroupId, ROW_GROUP_ID_BYTES);

long actualRowNumber = ByteBuffer.wrap(rowID).order(ByteOrder.LITTLE_ENDIAN).getLong();
assertEquals(actualRowNumber, rowNumber);
}
}

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