Is there any way to increase compute unit in building on-chain program of Solana

Question

I crashed with error of exceeding maximum unit of compute units while developing on-chain program of Solana. Is there any way to increase maximum compute unit?

Answer 1

If you're using solana-program-test to test your application, you can set higher or lower compute units using set_compute_max_units(), ie:

use solana_program_test::ProgramTest;
use crate::id;
use crate::processor::process_instruction;

let mut pt = ProgramTest::new("my_program", id(), processor!(process_instruction));
pt.set_compute_max_units(5_000_000);

Full example at https://github.com/solana-labs/solana-program-library/blob/78e29e9238e555967b9125799d7d420d7d12b959/token/program/tests/assert_instruction_count.rs#L24

For solana-test-validator, this isn't supported for now, but PRs are welcome!

Answer 2

The SDK for version 1.9.2 and greater does have changes for upping (or lowering) Compute Budget and Heap Size. In the solana repo in sdk/src/compute_budget.rs https://github.com/solana-labs/solana/blob/master/sdk/src/compute_budget.rs#L35

This should work for local testing but not yet enabled for devnet, mainnet-beta, etc.

The way it works is to create a request_units Instruction and put at the first instruction in the transaction:

/// Submits the program instruction as per the
/// instruction definition
fn submit_transaction(
    rpc_client: &RpcClient,
    wallet_signer: &dyn Signer,
    instructions: Vec<Instruction>,
) -> Result<Signature, Box<dyn std::error::Error>> {
    let mut transaction =
        Transaction::new_unsigned(Message::new(&instructions, Some(&wallet_signer.pubkey())));
    let recent_blockhash = rpc_client
        .get_latest_blockhash()
        .map_err(|err| format!("error: unable to get recent blockhash: {}", err))?;
    transaction
        .try_sign(&vec![wallet_signer], recent_blockhash)
        .map_err(|err| format!("error: failed to sign transaction: {}", err))?;

    let signature = rpc_client
        .send_and_confirm_transaction(&transaction)
        .map_err(|err| format!("error: send transaction: {}", err))?;
    Ok(signature)
}

/// 
fn foo() {
    // Other details omitted
    let accounts = &[];
    let instruction = Instruction::new_with_borsh(PROG_KEY, &0u8, accounts.to_vec());
    let bump_budget = ComputeBudgetInstruction::request_units(400_000u32);
    let txn = submit_transaction(
        &connection,
        &main_payer,
        [bump_budget, instruction.clone(), instruction.clone()].to_vec(),
    );

Notice in the log output that there is a drawdown for each instruction in rows 3 and 7:

[2022-02-05T09:08:49.715294000Z DEBUG solana_runtime::message_processor::stable_log] Program PWDnx8LkjJUn9bAVzG6Fp6BuvB41x7DkBZdo9YLMGcc invoke [1]
[2022-02-05T09:08:49.715522000Z DEBUG solana_runtime::message_processor::stable_log] Program log: process_instruction: PWDnx8LkjJUn9bAVzG6Fp6BuvB41x7DkBZdo9YLMGcc: 0 accounts, data=[0]
[2022-02-05T09:08:49.715551000Z DEBUG solana_runtime::message_processor::stable_log] Program PWDnx8LkjJUn9bAVzG6Fp6BuvB41x7DkBZdo9YLMGcc consumed 12843 of 400000 compute units
[2022-02-05T09:08:49.715675000Z DEBUG solana_runtime::message_processor::stable_log] Program PWDnx8LkjJUn9bAVzG6Fp6BuvB41x7DkBZdo9YLMGcc success
[2022-02-05T09:08:49.723680000Z DEBUG solana_runtime::message_processor::stable_log] Program PWDnx8LkjJUn9bAVzG6Fp6BuvB41x7DkBZdo9YLMGcc invoke [1]
[2022-02-05T09:08:49.723818000Z DEBUG solana_runtime::message_processor::stable_log] Program log: process_instruction: PWDnx8LkjJUn9bAVzG6Fp6BuvB41x7DkBZdo9YLMGcc: 0 accounts, data=[0]
[2022-02-05T09:08:49.723837000Z DEBUG solana_runtime::message_processor::stable_log] Program PWDnx8LkjJUn9bAVzG6Fp6BuvB41x7DkBZdo9YLMGcc consumed 12843 of 387157 compute units
[2022-02-05T09:08:49.724017000Z DEBUG solana_runtime::message_processor::stable_log] Program PWDnx8LkjJUn9bAVzG6Fp6BuvB41x7DkBZdo9YLMGcc success

Answer 3

You can refer to this tutorial from Solana Cookbook.

Note that you'll have to make the first instruction the one that sets the budget.

Sample snippet for Typescript:

const data = Buffer.from(
  Uint8Array.of(0, ...new BN(256000).toArray("le", 4))
);
const additionalComputeBudgetInstruction = new TransactionInstruction({
  keys: [],
  programId: new PublicKey("ComputeBudget111111111111111111111111111111"),
  data,
});
const transaction = new Transaction()
  .add(additionalComputeBudgetInstruction);