diff --git a/org.eclipse.jgit.pgm/src/org/eclipse/jgit/pgm/Log.java b/org.eclipse.jgit.pgm/src/org/eclipse/jgit/pgm/Log.java
index 048526ee8..688de2c49 100644
--- a/org.eclipse.jgit.pgm/src/org/eclipse/jgit/pgm/Log.java
+++ b/org.eclipse.jgit.pgm/src/org/eclipse/jgit/pgm/Log.java
@@ -267,6 +267,7 @@ protected void show(final RevCommit c) throws Exception {
 			outw.print(s);
 			outw.println();
 		}
+		c.disposeBody();
 
 		outw.println();
 		if (showNotes(c))
diff --git a/org.eclipse.jgit/src/org/eclipse/jgit/revwalk/RevCommit.java b/org.eclipse.jgit/src/org/eclipse/jgit/revwalk/RevCommit.java
index 37f1d7b8d..c23e4e328 100644
--- a/org.eclipse.jgit/src/org/eclipse/jgit/revwalk/RevCommit.java
+++ b/org.eclipse.jgit/src/org/eclipse/jgit/revwalk/RevCommit.java
@@ -609,7 +609,19 @@ public void reset() {
 		inDegree = 0;
 	}
 
-	final void disposeBody() {
+	/**
+	 * Discard the message buffer to reduce memory usage.
+	 * <p>
+	 * After discarding the memory usage of the {@code RevCommit} is reduced to
+	 * only the {@link #getTree()} and {@link #getParents()} pointers and the
+	 * time in {@link #getCommitTime()}. Accessing other properties such as
+	 * {@link #getAuthorIdent()}, {@link #getCommitterIdent()} or either message
+	 * function requires reloading the buffer by invoking
+	 * {@link RevWalk#parseBody(RevObject)}.
+	 *
+	 * @since 4.0
+	 */
+	public final void disposeBody() {
 		buffer = null;
 	}
 
diff --git a/org.eclipse.jgit/src/org/eclipse/jgit/revwalk/RevTag.java b/org.eclipse.jgit/src/org/eclipse/jgit/revwalk/RevTag.java
index 75201164c..bf2785e0d 100644
--- a/org.eclipse.jgit/src/org/eclipse/jgit/revwalk/RevTag.java
+++ b/org.eclipse.jgit/src/org/eclipse/jgit/revwalk/RevTag.java
@@ -270,7 +270,18 @@ public final String getTagName() {
 		return tagName;
 	}
 
-	final void disposeBody() {
+	/**
+	 * Discard the message buffer to reduce memory usage.
+	 * <p>
+	 * After discarding the memory usage of the {@code RevTag} is reduced to
+	 * only the {@link #getObject()} pointer and {@link #getTagName()}.
+	 * Accessing other properties such as {@link #getTaggerIdent()} or either
+	 * message function requires reloading the buffer by invoking
+	 * {@link RevWalk#parseBody(RevObject)}.
+	 *
+	 * @since 4.0
+	 */
+	public final void disposeBody() {
 		buffer = null;
 	}
 }