Merge pull request #8726 from vespa-engine/mpolden/limit-total-entries

Prevent log from growing unbounded within expiry

2 files changed, 10 insertions, 2 deletions

diff --git a/controller-server/src/main/java/com/yahoo/vespa/hosted/controller/auditlog/AuditLog.java b/controller-server/src/main/java/com/yahoo/vespa/hosted/controller/auditlog/AuditLog.java
index 3190ce7d332..c467a4a0acd 100644
--- a/controller-server/src/main/java/com/yahoo/vespa/hosted/controller/auditlog/AuditLog.java
+++ b/controller-server/src/main/java/com/yahoo/vespa/hosted/controller/auditlog/AuditLog.java
@@ -44,7 +44,13 @@ public class AuditLog {
         return new AuditLog(entries);
     }
 
-    /** Returns all entries in this. Entries are sorted descending by their timestamp */
+    /** Returns the first n entries in this. Since entries are sorted descendingly, this will be the n newest entries */
+    public AuditLog first(int n) {
+        if (entries.size() < n) return this;
+        return new AuditLog(entries.subList(0, n));
+    }
+
+    /** Returns all entries in this. Entries are sorted descendingly by their timestamp */
     public List<Entry> entries() {
         return entries;
     }
diff --git a/controller-server/src/main/java/com/yahoo/vespa/hosted/controller/auditlog/AuditLogger.java b/controller-server/src/main/java/com/yahoo/vespa/hosted/controller/auditlog/AuditLogger.java
index fcf33a92f79..7d8bbb17361 100644
--- a/controller-server/src/main/java/com/yahoo/vespa/hosted/controller/auditlog/AuditLogger.java
+++ b/controller-server/src/main/java/com/yahoo/vespa/hosted/controller/auditlog/AuditLogger.java
@@ -25,6 +25,7 @@ public class AuditLogger {
 
     /** The TTL of log entries. Entries older than this will be removed when the log is updated */
     private static final Duration entryTtl = Duration.ofDays(14);
+    private static final int maxEntries = 2000;
 
     private final CuratorDb db;
     private final Clock clock;
@@ -71,7 +72,8 @@ public class AuditLogger {
         try (Lock lock = db.lockAuditLog()) {
             AuditLog auditLog = db.readAuditLog()
                                   .pruneBefore(now.minus(entryTtl))
-                                  .with(entry);
+                                  .with(entry)
+                                  .first(maxEntries);
             db.writeAuditLog(auditLog);
         }