Limits & Specs
VM specifications
| Spec | Value |
|---|---|
| Instance type | GCP e2-medium |
| vCPUs | 2 |
| RAM | 4 GB |
| Swap | 2 GB |
| Disk | 10-15 GB persistent SSD |
| OS | Ubuntu 22.04 LTS |
Account limits
| Limit | Value |
|---|---|
| VMs per user | 1 |
| Price | Free during early access |
Session limits
| Limit | Value |
|---|---|
| Scrollback history | 5000 lines per pane |
| Idle timeout | 60 minutes (default) |
| Resume time | ~30 seconds (from suspend) |
| Cold start time | ~60 seconds (from stopped) |
| Split panes | No hard limit (practical limit depends on screen size) |
Networking limits
| Limit | Value |
|---|---|
| Inbound ports | Only port 80 from Cloudflare |
| Port forwarding range | 1024-65535 |
| Blocked ports | Below 1024, port 3001 |
| Outbound | Unrestricted |
Memory management thresholds
| Threshold | Action |
|---|---|
| 80% (RAM + swap) | Warning banner shown in terminal |
| 85% | tmux scrollback buffers cleared |
| 90% | Largest user process killed |
| 95% | Terminal server restarted (tmux sessions survive) |
WebSocket connection
| Parameter | Value |
|---|---|
| Protocol-level ping interval | 30 seconds |
| Application-level ping interval | 30 seconds |
| Application-level pong timeout | 90 seconds |
| Heartbeat (activity report) interval | 60 seconds |
| Auto-reconnect delay | 2 seconds |
What persists across VM suspend/resume
- All running processes (RAM preserved to disk)
- tmux sessions and their full state
- All files on disk
- Installed packages and system configuration
- Environment variables in running shells
- Shell history
- Split pane layout
What persists across VM stop/start (cold restart)
- All files on disk
- Installed packages and system configuration
- Shell history (in
~/.bash_history) - Custom configuration (
.bashrc,.profile, etc.)
What does NOT persist across VM stop/start
- Running processes (all processes terminate)
- tmux sessions (they must be recreated)
- Environment variables set in running shells (but those in
.bashrcare reloaded) - Temporary files in
/tmp
Disk space
The VM disk is persistent and survives suspend, resume, stop, and start operations. Space is shared between the OS, MoltShell infrastructure, and your files.
To check available space:
bash
df -h /To find what is using space:
bash
du -sh ~/* | sort -rh | head -20If you run out of disk space, remove large files or unused packages:
bash
sudo apt autoremove -y
sudo apt clean
npm cache clean --force