How do I diagnose a freeze in my game?

Diagnose a freeze by capturing where the game hangs and what it was doing, identifying the affected devices and conditions, and finding the cause. Step one, capture: a freeze is the game becoming unresponsive (not a clean crash), so capture the state it was in and the events leading up to the hang, since a freeze gives less to go on than a crash, knowing what it was doing when it froze is key. Step two, identify devices and conditions: see whether the freeze clusters on certain hardware (a performance or driver issue) or follows specific actions or states, which narrows the cause. Step three, find the cause: freezes commonly come from a blocked main thread (a long operation on the thread that should stay responsive), an infinite loop, a deadlock, or severe performance degradation, use the captured state and conditions to identify which. On mobile, a freeze often becomes an ANR (the OS kills an unresponsive app), which gives you a capture point. Bugnet helps: it captures the breadcrumbs and context leading up to a freeze (and any ANR or crash it triggers), tags by device, and groups by signature, so you see what the game was doing and on what devices it hangs, pointing to the cause, which is how you diagnose a freeze in your game.

What causes a game to freeze?

A game freezes (becomes unresponsive without crashing) usually because something blocks the thread that should keep the game responsive, or the game gets stuck. Common causes: a blocked main thread (a long-running operation, loading, heavy computation, a synchronous network or disk call, running on the main/UI thread, so the game cannot update or respond until it finishes), an infinite loop (the game gets stuck repeating forever), a deadlock (two parts of the game each waiting for the other, so neither proceeds), severe performance degradation (the game slows to the point of seeming frozen, sometimes from memory pressure or an overwhelming workload), or waiting on something that never completes (a resource, a response). The common thread is that the game is stuck or blocked rather than having cleanly failed, which is why it freezes rather than crashes. On mobile, a sustained freeze often triggers an ANR (Application Not Responding), where the OS kills the unresponsive app. To diagnose which cause you have, you need to know what the game was doing when it froze. Bugnet helps capture that: it records the breadcrumbs leading up to the freeze and the context of any ANR or crash it triggers, so you can see what the game was doing when it hung, pointing toward the cause, which is what causes a game to freeze and how to investigate.

What's the difference between a freeze and a crash?

A crash is when the game terminates unexpectedly (it stops running, often with an error and stack trace); a freeze (or hang) is when the game keeps running but becomes unresponsive (it does not respond to input or update, appearing stuck). The key difference is that a crash is a clean failure, the game ends, and typically you get a stack trace pointing to where it failed, while a freeze is the game getting stuck or blocked without ending, so it just stops responding, often with less immediate diagnostic information. Causes differ too: crashes come from errors (unhandled exceptions, invalid memory access, assertion failures), while freezes come from blocking (a blocked main thread, an infinite loop, a deadlock) or severe slowdown. Freezes can be harder to diagnose because there is no clean crash point, you need to know what the game was doing when it hung. On mobile, a sustained freeze often becomes an ANR (the OS kills the unresponsive app), which converts it into a capture-able event. For both, knowing the state and events leading up to the failure is valuable. Bugnet captures that context, breadcrumbs and conditions for crashes and for freezes that trigger an ANR or crash, so you can diagnose both, which is the difference between a freeze and a crash and how to approach each.

Steps to Diagnose a Freeze

Quick answer: To diagnose a freeze: capture where the game hangs and what it was doing, identify the affected devices and conditions, and find the cause (often a blocked main thread or loop).

A freeze leaves the game unresponsive without a clean crash. These are the steps to diagnose one.

Step 1: Capture Where the Game Hangs

Start by capturing where the game hangs and what it was doing: a freeze is the game becoming unresponsive (not a clean crash), so you want to know the state it was in and the events leading up to the hang. Capturing what was happening when it froze is the key first step, since a freeze gives less to go on than a crash.

Bugnet helps via breadcrumbs and context: the trail of events leading up to the freeze (and any crash it eventually triggers, such as an ANR on mobile, where the OS kills an unresponsive app) shows what the game was doing when it hung, giving you the context to start diagnosing a freeze.

Step 2: Identify Affected Devices and Conditions

Next, identify which devices and conditions trigger the freeze: does it cluster on certain hardware (a performance or driver issue), or after specific actions or states? The conditions narrow down the cause, distinguishing, say, a performance-related freeze on low-end devices from a logic-related hang triggered by a specific action.

Bugnet shows the conditions: when a freeze manifests as an ANR or crash, Bugnet tags it with device and OS and groups occurrences by signature, so you see whether the freeze clusters on certain hardware or follows certain sequences, pointing toward a performance cause or a specific triggering condition.

Step 3: Find the Cause

Finally, find the cause: freezes commonly come from a blocked main thread (a long operation running on the thread that should stay responsive), an infinite loop, a deadlock, or severe performance degradation. Using the state and conditions you captured, identify which is happening so you can fix it (move work off the main thread, fix the loop, resolve the deadlock).

Bugnet supports finding the cause by showing what preceded the freeze: the breadcrumb sequence and conditions point to what the game was doing when it hung (loading, a heavy operation, a specific action), helping you identify whether it is a blocked main thread, a loop, or a performance issue, and verify per version once you fix it.

To diagnose a freeze: capture where the game hangs and what it was doing, identify the affected devices and conditions, and find the cause (often a blocked main thread, loop, or deadlock), a freeze is a hang, so capturing what it was doing is key.