From cb83c178113b6869de7aad6fb1fb16d81687f076 Mon Sep 17 00:00:00 2001
From: Andrea Cavalli <andrea@cavallium.it>
Date: Wed, 30 Mar 2022 18:36:07 +0200
Subject: [PATCH] Bugfixes

---
 .../database/disk/AbstractRocksDBColumn.java    |  6 +++---
 .../database/disk/OptimisticRocksDBColumn.java  | 17 +++++++++++++++--
 2 files changed, 18 insertions(+), 5 deletions(-)

diff --git a/src/main/java/it/cavallium/dbengine/database/disk/AbstractRocksDBColumn.java b/src/main/java/it/cavallium/dbengine/database/disk/AbstractRocksDBColumn.java
index ef9498f..b6e2087 100644
--- a/src/main/java/it/cavallium/dbengine/database/disk/AbstractRocksDBColumn.java
+++ b/src/main/java/it/cavallium/dbengine/database/disk/AbstractRocksDBColumn.java
@@ -69,7 +69,8 @@ public sealed abstract class AbstractRocksDBColumn<T extends RocksDB> implements
 	private final BufferAllocator alloc;
 	private final ColumnFamilyHandle cfh;
 
-	private final MeterRegistry meterRegistry;
+	protected final MeterRegistry meterRegistry;
+	protected final String columnName;
 
 	protected final DistributionSummary keyBufferSize;
 	protected final DistributionSummary readValueNotFoundWithoutBloomBufferSize;
@@ -99,14 +100,13 @@ public sealed abstract class AbstractRocksDBColumn<T extends RocksDB> implements
 		this.nettyDirect = opts.allowNettyDirect() && alloc.getAllocationType() == OFF_HEAP;
 		this.alloc = alloc;
 		this.cfh = cfh;
-
 		String columnName;
 		try {
 			columnName = new String(cfh.getName(), StandardCharsets.UTF_8);
 		} catch (RocksDBException e) {
 			throw new IllegalStateException(e);
 		}
-
+		this.columnName = columnName;
 		this.meterRegistry = meterRegistry;
 
 		this.keyBufferSize = DistributionSummary
diff --git a/src/main/java/it/cavallium/dbengine/database/disk/OptimisticRocksDBColumn.java b/src/main/java/it/cavallium/dbengine/database/disk/OptimisticRocksDBColumn.java
index d8611de..ec64754 100644
--- a/src/main/java/it/cavallium/dbengine/database/disk/OptimisticRocksDBColumn.java
+++ b/src/main/java/it/cavallium/dbengine/database/disk/OptimisticRocksDBColumn.java
@@ -2,6 +2,7 @@ package it.cavallium.dbengine.database.disk;
 
 import static it.cavallium.dbengine.database.LLUtils.MARKER_ROCKSDB;
 
+import io.micrometer.core.instrument.DistributionSummary;
 import io.micrometer.core.instrument.MeterRegistry;
 import io.netty5.buffer.api.Buffer;
 import io.netty5.buffer.api.BufferAllocator;
@@ -20,6 +21,7 @@ import org.jetbrains.annotations.Nullable;
 import org.rocksdb.ColumnFamilyHandle;
 import org.rocksdb.OptimisticTransactionDB;
 import org.rocksdb.ReadOptions;
+import org.rocksdb.RocksDB;
 import org.rocksdb.RocksDBException;
 import org.rocksdb.Status.Code;
 import org.rocksdb.Transaction;
@@ -31,13 +33,23 @@ public final class OptimisticRocksDBColumn extends AbstractRocksDBColumn<Optimis
 
 	private static final boolean ALWAYS_PRINT_OPTIMISTIC_RETRIES = false;
 
+	private final DistributionSummary optimisticAttempts;
+
 	public OptimisticRocksDBColumn(OptimisticTransactionDB db,
 			DatabaseOptions databaseOptions,
 			BufferAllocator alloc,
-			String dbName,
+			String databaseName,
 			ColumnFamilyHandle cfh,
 			MeterRegistry meterRegistry) {
-		super(db, databaseOptions, alloc, dbName, cfh, meterRegistry);
+		super(db, databaseOptions, alloc, databaseName, cfh, meterRegistry);
+		this.optimisticAttempts = DistributionSummary
+				.builder("db.optimistic.attempts.distribution")
+				.publishPercentiles(0.2, 0.5, 0.95)
+				.baseUnit("times")
+				.scale(1)
+				.publishPercentileHistogram()
+				.tags("db.name", databaseName, "db.column", columnName)
+				.register(meterRegistry);
 	}
 
 	@Override
@@ -184,6 +196,7 @@ public final class OptimisticRocksDBColumn extends AbstractRocksDBColumn<Optimis
 					if (retries > 5) {
 						logger.warn(MARKER_ROCKSDB, "Took {} retries to update key {}", retries, LLUtils.toStringSafe(key));
 					}
+					optimisticAttempts.record(retries);
 					return switch (returnMode) {
 						case NOTHING -> {
 							if (sentPrevData != null) {