How to Fix RPC Calls Feeling Laggy in Multiplayer

Laggy RPCs are waiting on the round-trip. Local prediction fixes the feel. Here is how.

How to fix it

1. Predict locally and reconcile

Show the result of an action immediately on the client and send the RPC to the server, reconciling if the server disagrees. Waiting for the RPC to return before responding adds the full latency to every action.

2. Use unreliable for frequent actions

Frequent, non-critical actions (firing, movement) can use unreliable RPCs that do not wait for acknowledgment, so they are not delayed by reliable ordering. Reserve reliable RPCs for actions that must not be lost.

3. Avoid blocking on reliable order

Reliable, ordered RPCs can stall behind a lost packet (head-of-line blocking), delaying everything after it. Do not route responsiveness-critical actions through a heavily-loaded reliable ordered channel.

Catching the ones you can't reproduce

The hardest version of this to fix is the one you can't reproduce — it only happens on a player's hardware, OS, driver, or save state, under conditions that simply aren't present on your machine. A report that says “it crashed” or “it froze” gives you nothing to act on, so the bug survives release after release while quietly costing you players.

Automatic error capture closes that gap. Each failure arrives with its full stack trace, the device and OS, the build number, and a breadcrumb trail of what the player did right before it broke, so even a failure you have never seen becomes a specific, reproducible issue. Fold identical failures into one signature ranked by how many players each hits, and your worklist sorts itself worst-first instead of arriving as a stream of vague complaints.

This is where a tool like Bugnet earns its place. Its SDK captures every error automatically with the full stack trace plus device, OS, memory, build, and game-state context, folds duplicates into one grouped issue with an occurrence count, and ties each to the build it first appeared on — so you fix the problem that hurts the most players first and confirm it is gone when its signature disappears from the next release.