singhpk234 commented on code in PR #1517:
URL: https://github.com/apache/polaris/pull/1517#discussion_r2074454437


##########
extension/persistence/relational-jdbc/src/main/java/org/apache/polaris/extension/persistence/relational/jdbc/DatasourceOperations.java:
##########
@@ -173,23 +190,82 @@ public int executeUpdate(String query) throws 
SQLException {
    * @throws SQLException : Exception caught during transaction execution.
    */
   public void runWithinTransaction(TransactionCallback callback) throws 
SQLException {
-    try (Connection connection = borrowConnection()) {
-      boolean autoCommit = connection.getAutoCommit();
-      connection.setAutoCommit(false);
-      boolean success = false;
+    withRetries(
+        () -> {
+          try (Connection connection = borrowConnection()) {
+            boolean autoCommit = connection.getAutoCommit();
+            boolean success = false;
+            connection.setAutoCommit(false);
+            try {
+              try (Statement statement = connection.createStatement()) {
+                success = callback.execute(statement);
+              }
+            } finally {
+              if (success) {
+                connection.commit();
+              } else {
+                connection.rollback();
+              }
+              connection.setAutoCommit(autoCommit);
+            }
+          }
+          return null;
+        });
+  }
+
+  private boolean isRetryable(SQLException e) {
+    String sqlState = e.getSQLState();
+
+    if (sqlState != null) {
+      return sqlState.equals(DEADLOCK_SQL_CODE)
+          || // Deadlock detected
+          sqlState.equals(SERIALIZATION_FAILURE_SQL_CODE); // Serialization 
failure
+    }
+
+    // Additionally, one might check for specific error messages or other 
conditions
+    return e.getMessage().contains("connection refused")
+        || e.getMessage().contains("connection reset");
+  }
+
+  public <T> T withRetries(Operation<T> operation) throws SQLException {
+    int attempts = 0;
+    // maximum number of retries.
+    int maxAttempts = relationalJdbcConfiguration.maxRetries().orElse(1);
+    // How long we should try, since the first attempt.
+    long maxDuration = 
relationalJdbcConfiguration.maxDurationInMs().orElse(100L);
+    // How long to wait before first failure.
+    long delay = relationalJdbcConfiguration.initialDelayInMs().orElse(100L);
+
+    // maximum time we will retry till.
+    long maxRetryTime = Instant.now().toEpochMilli() + maxDuration;
+
+    while (attempts < maxAttempts) {
       try {
-        try (Statement statement = connection.createStatement()) {
-          success = callback.execute(statement);
+        return operation.execute();
+      } catch (SQLException e) {
+        attempts++;
+        long timeLeft = Math.max((maxRetryTime - 
Instant.now().toEpochMilli()), 0L);
+        if (attempts >= maxAttempts || !isRetryable(e) || timeLeft == 0) {
+          throw e;
         }
-      } finally {
-        if (success) {
-          connection.commit();
-        } else {
-          connection.rollback();
+        // Add jitter
+        long timeToSleep = Math.min(timeLeft, delay + (long) 
(random.nextDouble() * 0.2 * delay));

Review Comment:
   delay is not a fixed component, it raises with the exponent of 2 essentialy 
its (2^ attempt) so essentially the jitter we have is 
   
   random value between ((2 ^ attempt), (2 ^ (attempt + 1) * 0.2) ], this we do 
both both exponential backoff as well not exactly have collisions. 
   
   0 sleep time will not be possible as both timeLeft and delay + (long) 
(random.nextDouble() * 0.2 * delay))  > 0 
   
   please let me know your thoughts considering above.



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