# Async Operations & Locking

Since the graph database handles high-concurrency workloads, many operations are asynchronous to avoid blocking threads.

If you are processing a large result set, consider using AsEnumerableAsync(). This method parallelizes the reading of data from disk, which can significantly improve performance for heavy queries.

await foreach (var node in Graph.Query().StartAt("Log").AsEnumerableAsync())
{
    // Process one by one without buffering everything in memory
    await ProcessLogAsync(node);
}

When modifying the graph, you must use async methods to acquire locks. This ensures thread safety and prevents data corruption.

To modify a node, you must follow this specific pattern:

1. Acquire Lock: Use TryGetLockedAsync or GetOrAddLockedAsync to get a LockedNode.
2. Modify: Perform your updates on the LockedNode object.
3. Commit: Call CommitAsync to save changes and release the lock.

Locks are exclusive. While you hold a lock on a node, no other thread can read or write to it. Keep your critical sections (the time between lock and commit) as short as possible.

// 1. Acquire Lock
var lockedNode = await Graph.TryGetLockedAsync(someUID);

if (lockedNode != null)
{
    try
    {
        // 2. Modify
        // Perform logic that might throw exceptions here
        lockedNode.UpdateProperty("visited", true);

        // 3. Commit
        await Graph.CommitAsync(lockedNode);
    }
    catch (Exception)
    {
        // If something goes wrong, abandon changes to release the lock
        Graph.AbandonChanges(lockedNode);
        throw;
    }
}

• ReadOnlyNode: Lightweight, safe for reading. Returned by queries.
• LockedNode: Heavyweight, represents exclusive access to a node for modification.

The CommitAsync method pushes changes to the storage engine and releases the lock.

// Commit single node
await Graph.CommitAsync(node);

// Commit multiple nodes (atomically)
await Graph.CommitAsync(nodeA, nodeB);

If you modify a node but decide not to save (e.g., validation failed), use AbandonChanges(node).