Instruction Limits
The Internet Computer uses WebAssembly as the platform for executing messages of smart contracts. Since WebAssembly is Turing-complete, it can express different kinds of computations including non-terminating computations. The Internet Computer protects against non-terminating computations by limiting the number of WebAssembly instructions per message execution. The instruction limit depends on the message type as shown in the following table.
| Message type | Instruction limit |
|---|---|
| Update messages | 20 billion instructions |
| Query messages | 5 billion instructions |
| Heartbeats and timers | 5 billion instructions |
| Canister install and upgrade | 200 billion instructions |
Notes:
- The instruction limit for update messages, heartbeats, and timers is planned to be raised to 30 billion instructions in near future.