Add database statistics to GlobalStatistics (#5208)

Add database statistics to GlobalStatistics

osu.Game/Database/DatabaseContextFactory.cs

@@ -5,6 +5,7 @@ using System.Linq;
 using System.Threading;
 using Microsoft.EntityFrameworkCore.Storage;
 using osu.Framework.Platform;
+using osu.Framework.Statistics;
 
 namespace osu.Game.Database
 {
@@ -31,11 +32,20 @@ namespace osu.Game.Database
             recycleThreadContexts();
         }
 
+        private static readonly GlobalStatistic<int> reads = GlobalStatistics.Get<int>("Database", "Get (Read)");
+        private static readonly GlobalStatistic<int> writes = GlobalStatistics.Get<int>("Database", "Get (Write)");
+        private static readonly GlobalStatistic<int> commits = GlobalStatistics.Get<int>("Database", "Commits");
+        private static readonly GlobalStatistic<int> rollbacks = GlobalStatistics.Get<int>("Database", "Rollbacks");
+
         /// <summary>
         /// Get a context for the current thread for read-only usage.
         /// If a <see cref="DatabaseWriteUsage"/> is in progress, the existing write-safe context will be returned.
         /// </summary>
-        public OsuDbContext Get() => threadContexts.Value;
+        public OsuDbContext Get()
+        {
+            reads.Value++;
+            return threadContexts.Value;
+        }
 
         /// <summary>
         /// Request a context for write usage. Can be consumed in a nested fashion (and will return the same underlying context).
@@ -45,6 +55,7 @@ namespace osu.Game.Database
         /// <returns>A usage containing a usable context.</returns>
         public DatabaseWriteUsage GetForWrite(bool withTransaction = true)
         {
+            writes.Value++;
             Monitor.Enter(writeLock);
             OsuDbContext context;
 
@@ -90,9 +101,15 @@ namespace osu.Game.Database
                 if (usages == 0)
                 {
                     if (currentWriteDidError)
+                    {
+                        rollbacks.Value++;
                         currentWriteTransaction?.Rollback();
+                    }
                     else
+                    {
+                        commits.Value++;
                         currentWriteTransaction?.Commit();
+                    }
 
                     if (currentWriteDidWrite || currentWriteDidError)
                     {

osu.Game/Database/OsuDbContext.cs

@@ -6,6 +6,7 @@ using Microsoft.EntityFrameworkCore;
 using Microsoft.EntityFrameworkCore.Diagnostics;
 using Microsoft.Extensions.Logging;
 using osu.Framework.Logging;
+using osu.Framework.Statistics;
 using osu.Game.Beatmaps;
 using osu.Game.Configuration;
 using osu.Game.IO;
@@ -34,6 +35,8 @@ namespace osu.Game.Database
 
         private static readonly Lazy<OsuDbLoggerFactory> logger = new Lazy<OsuDbLoggerFactory>(() => new OsuDbLoggerFactory());
 
+        private static readonly GlobalStatistic<int> contexts = GlobalStatistics.Get<int>("Database", "Contexts");
+
         static OsuDbContext()
         {
             // required to initialise native SQLite libraries on some platforms.
@@ -76,6 +79,8 @@ namespace osu.Game.Database
                 connection.Close();
                 throw;
             }
+
+            contexts.Value++;
         }
 
         ~OsuDbContext()
@@ -85,6 +90,20 @@ namespace osu.Game.Database
             Dispose();
         }
 
+        private bool isDisposed;
+
+        public override void Dispose()
+        {
+            if (isDisposed) return;
+
+            isDisposed = true;
+
+            base.Dispose();
+
+            contexts.Value--;
+            GC.SuppressFinalize(this);
+        }
+
         protected override void OnConfiguring(DbContextOptionsBuilder optionsBuilder)
         {
             base.OnConfiguring(optionsBuilder);