opencode utilization at 99-100% randomly - opencode unresponsive

[tokkenT]

Description

Periodically opencode cli process hits 99-100% cpu utilization. Resulting in fans kicking in. Also, results in the cli not able to take any keyboard inputs. Essentially dead. Uncertain what exactly it is being done with this.

Started using opencode since 1.3.3. - this wasn't an issue
first noted in 1.15.x version have
also issue in 1.16.x

Only fix is it close terminal or kill opencode process

Plugins

No response

OpenCode version

1.15.11

Steps to reproduce

1. use opencode
2. leave or use
3. randomly results in 99-100% cpu utilization

not able to reproduce since not sure what triggers it.
notice that the longer the open session (which is essentially always until this spike occurs)

Updated Summary: (edited 2026-06-25 2:58PM)

• 1.15.11

• cpu spikes to over 98% randomly, even when not using opencode just idle in the background

• keystrokes are nonresponse in cli

• 5 minutes tested with no self resolution

• randomly, can't switch from build to plan or vice versa

• 1.17.11

• runs at 100-300% CPU utilization for very minor requests vs 1.15.11 that uses 50-65% CPU utilization

• results aren't that much better than 1.15.13

Screenshot and/or share link

No response

Operating System

No response

Terminal

macOS terminal

[github-actions]

---

This issue might be a duplicate of existing issues. Please check:

• opencode spins one CPU core at ~100% indefinitely after bootstrap (no logs, no I/O, ignores SIGTERM) #32965: opencode spins one CPU core at ~100% indefinitely after bootstrap
• opencode is using CPU for doing nothing! #19466: opencode is using CPU for doing nothing!
• [Bug] High CPU and Memory usage on macOS ARM64 #30126: High CPU and Memory usage on macOS ARM64
• OpenCode is heavily cpu-bound #21470: OpenCode is heavily cpu-bound
• Fans being very loud when opening OpenCode, other apps are fine #17843: Fans being very loud when opening OpenCode (high CPU on Mac)

If your issue is the same as one of the above, please add a comment there with any additional details rather than opening a new issue.

[tokkenT]

upgrade to [v1.17.9] result in cpu usage at 191%

• noted that it was when system was idle.

[tokkenT]

a few tests:

• 1.3.17 seems to be fine
• 1.3.x seems to be fine
  1.14.0 issue is present
• 1.3.x - issue is present
• 1.14.7 issue is present
• 1.14.x - issue is present
• 1.15.x issue is present
• 1.16.x issue is present
• 1.17.x issue is present - shows a 191% utilization

no way to exit out of issue. have to force quit and session context is lost.

[simonklee]

The next OpenCode release uses OpenTUI v0.4.2. This release fixes a possible cause of blocked input in the macOS threaded terminal renderer.

The original issue happens intermittently, and its hard to reproduce reliably. As a result, I cannot confirm that this renderer bug caused the CPU spike and keyboard freeze.

If you experienced this issue, please test a build that uses OpenTUI v0.4.2. Let us know whether the CPU spike or keyboard freeze happens again.

If OpenCode becomes unresponsive, capture a process sample while the problem is active:

sample <pid> 10 -file opencode-sample.txt

Attach the sample and include:

• Your OS version
• Your terminal and version

[tokkenT]

also noticed that opencode CPU for v1.17.11 is 100-300% (constantly) CPU had to downgrade to 1.15.11.

• which still has random opencode usage that goes over 100%
• cli freezes for inputs but the CPU utilization is consistently under 100 (20-60% spikes)

[tokkenT]

@simonklee - attached is the spin dump where opencode process was >96.8% to 99 % cpu utilization

• system was not using opencode for hours prior to this.
• cli was in the background unused for hours
• spike remained this high for minutes for no reason
• cli was nonresponse, no keyboard stroke taken.
• esc key not working either
• opencode cli nonresponse at all.
• had to force quit cli after 5 minutes of no self resolution

after force quit issue

spindump - 2026-06-25 1448.txt

(url)

[tokkenT]

this is random and when the opencode cli is idle.

Unfortunately there is no recovery from this a force quit of opencode process that result in the opencode cli outputting characters continuously and the context window is lost. The terminal with the cli has to be closed and is useable when this occurs.