Refactor linear page cache history tracer to have separate tracers fo…

…r global and cursor local events.

Add support for cursor events tracers.

community/io/src/test/java/org/neo4j/io/pagecache/PageCacheSlowTest.java

@@ -40,9 +40,9 @@
 import org.neo4j.io.fs.FileSystemAbstraction;
 import org.neo4j.io.pagecache.tracing.PageCacheTracer;
 import org.neo4j.io.pagecache.tracing.cursor.PageCursorTracerSupplier;
-import org.neo4j.test.LinearHistoryPageCacheTracer;
+import org.neo4j.io.pagecache.tracing.linear.LinearHistoryTracerFactory;
+import org.neo4j.io.pagecache.tracing.linear.LinearTracers;
 import org.neo4j.test.rule.RepeatRule;
-import org.neo4j.test.LinearHistoryPageCursorTracer;
 
 import static org.hamcrest.Matchers.instanceOf;
 import static org.hamcrest.Matchers.is;
@@ -454,9 +454,9 @@ public void pageCacheMustRemainInternallyConsistentWhenGettingRandomFailures() t
 
         // Because our test failures are non-deterministic, we use this tracer to capture a full history of the
         // events leading up to any given failure.
-        LinearHistoryPageCacheTracer tracer = new LinearHistoryPageCacheTracer();
-        //TODO:sdfasdf
-        getPageCache( fs, maxPages, pageCachePageSize, tracer, LinearHistoryPageCursorTracer::new );
+        LinearTracers linearTracers = LinearHistoryTracerFactory.pageCacheTracer();
+        getPageCache( fs, maxPages, pageCachePageSize, linearTracers.getPageCacheTracer(),
+                linearTracers.getCursorTracerSupplier() );
 
         PagedFile pfA = pageCache.map( existingFile( "a" ), filePageSize );
         PagedFile pfB = pageCache.map( existingFile( "b" ), filePageSize / 2 + 1 );
@@ -525,7 +525,7 @@ public void pageCacheMustRemainInternallyConsistentWhenGettingRandomFailures() t
         }
         catch ( Throwable e )
         {
-            tracer.printHistory( System.err );
+            linearTracers.printHistory( System.err );
             throw e;
         }
     }

community/io/src/test/java/org/neo4j/io/pagecache/randomharness/RandomPageCacheTestHarness.java

@@ -44,7 +44,10 @@
 import org.neo4j.io.pagecache.impl.SingleFilePageSwapperFactory;
 import org.neo4j.io.pagecache.impl.muninn.MuninnPageCache;
 import org.neo4j.io.pagecache.tracing.PageCacheTracer;
+import org.neo4j.io.pagecache.tracing.cursor.DefaultPageCursorTracerSupplier;
 import org.neo4j.io.pagecache.tracing.cursor.PageCursorTracerSupplier;
+import org.neo4j.io.pagecache.tracing.linear.LinearHistoryPageCacheTracerTest;
+import org.neo4j.io.pagecache.tracing.linear.LinearTracers;
 
 /**
  * The RandomPageCacheTestHarness can plan and run random page cache tests, repeatably if necessary, and verify that
@@ -54,7 +57,7 @@
  * before and after executing the planned test respectively, and it can integrate with the adversarial file system
  * for fault injection, and arbitrary PageCacheTracers.
  *
- * See {@link org.neo4j.test.LinearHistoryPageCacheTracerTest} for an example of how to configure and use the harness.
+ * See {@link LinearHistoryPageCacheTracerTest} for an example of how to configure and use the harness.
  */
 public class RandomPageCacheTestHarness implements Closeable
 {
@@ -92,7 +95,7 @@ public RandomPageCacheTestHarness()
         filePageCount = cachePageCount * 10;
         filePageSize = cachePageSize;
         tracer = PageCacheTracer.NULL;
-        cursorTracerSupplier = PageCursorTracerSupplier.NULL;
+        cursorTracerSupplier = DefaultPageCursorTracerSupplier.INSTANCE;
         commandCount = 1000;
 
         Command[] commands = Command.values();
@@ -150,6 +153,14 @@ public void setTracer( PageCacheTracer tracer )
         this.tracer = tracer;
     }
 
+    /**
+     * Set the page cursor tracers supplier.
+     */
+    public void setCursorTracerSupplier( PageCursorTracerSupplier cursorTracerSupplier )
+    {
+        this.cursorTracerSupplier = cursorTracerSupplier;
+    }
+
     /**
      * Set the mischief rate for the adversarial file system.
      */
@@ -227,7 +238,7 @@ public void setCommandCount( int commandCount )
     /**
      * Set the preparation phase to use. This phase is executed before all the planned commands. It can be used to
      * prepare some file contents, or reset some external state, such as the
-     * {@link org.neo4j.test.LinearHistoryPageCacheTracer}.
+     * {@link LinearTracers}.
      *
      * The preparation phase is executed before each iteration.
      */