Index: oak-segment-tar/src/main/java/org/apache/jackrabbit/oak/segment/file/AbstractFileStore.java
===================================================================
--- oak-segment-tar/src/main/java/org/apache/jackrabbit/oak/segment/file/AbstractFileStore.java	(revision 1814560)
+++ oak-segment-tar/src/main/java/org/apache/jackrabbit/oak/segment/file/AbstractFileStore.java	(working copy)
@@ -29,6 +29,7 @@
 import java.util.Set;
 import java.util.UUID;
 import java.util.concurrent.ExecutionException;
+import java.util.concurrent.atomic.AtomicInteger;
 
 import javax.annotation.CheckForNull;
 import javax.annotation.Nonnull;
@@ -129,11 +130,14 @@
 
     protected final IOMonitor ioMonitor;
 
+    static final AtomicInteger segmentIdAllocations = new AtomicInteger();
+
     AbstractFileStore(final FileStoreBuilder builder) {
         this.directory = builder.getDirectory();
         this.tracker = new SegmentTracker(new SegmentIdFactory() {
             @Override @Nonnull
             public SegmentId newSegmentId(long msb, long lsb) {
+                segmentIdAllocations.incrementAndGet();
                 return new SegmentId(AbstractFileStore.this, msb, lsb, segmentCache::recordHit);
             }
         });
Index: oak-segment-tar/src/main/java/org/apache/jackrabbit/oak/segment/file/FileStore.java
===================================================================
--- oak-segment-tar/src/main/java/org/apache/jackrabbit/oak/segment/file/FileStore.java	(revision 1814560)
+++ oak-segment-tar/src/main/java/org/apache/jackrabbit/oak/segment/file/FileStore.java	(working copy)
@@ -59,6 +59,7 @@
 import java.util.concurrent.ExecutionException;
 import java.util.concurrent.TimeUnit;
 import java.util.concurrent.atomic.AtomicBoolean;
+import java.util.concurrent.atomic.AtomicInteger;
 import java.util.concurrent.atomic.AtomicLong;
 import java.util.function.Consumer;
 
@@ -164,6 +165,8 @@
     @Nonnull
     private final SegmentNotFoundExceptionListener snfeListener;
 
+    private static final AtomicInteger uncachedSegmentReads = new AtomicInteger();
+
     FileStore(final FileStoreBuilder builder) throws InvalidFileStoreVersionException, IOException {
         super(builder);
 
@@ -477,6 +480,8 @@
         fileReaper.reap();
 
         log.info("TarMK closed: {}", directory);
+        log.info("TarMK segment ID allocations: {}", segmentIdAllocations);
+        log.info("TarMK uncached segment reads: {}", uncachedSegmentReads);
     }
 
     @Override
@@ -490,7 +495,10 @@
     @Nonnull
     public Segment readSegment(final SegmentId id) {
         try (ShutDownCloser ignored = shutDown.keepAlive()) {
-            return segmentCache.getSegment(id, () -> readSegmentUncached(tarFiles, id));
+            return segmentCache.getSegment(id, () -> {
+                uncachedSegmentReads.incrementAndGet();
+                return readSegmentUncached(tarFiles, id);
+            });
         } catch (ExecutionException e) {
             SegmentNotFoundException snfe = asSegmentNotFoundException(e, id);
             snfeListener.notify(id, snfe);