Frais de priorité et budget de calcul

import { ComputeBudgetProgram } from "@solana/web3.js";

const tx = new Transaction()
  .add(ComputeBudgetProgram.setComputeUnitLimit({ units: 250_000 }))
  .add(ComputeBudgetProgram.setComputeUnitPrice({ microLamports: 50_000 }))
  .add(yourRaydiumSwapIx);

wrap_sol (create_ata + system transfer + sync_native)   ≈ 30 000
CPMM swap_base_input (SPL)                              ≈ 140 000
close_account (unwrap)                                  ≈ 5 000
ComputeBudget instructions                              ≈ 10 000
────────────────────────────────────────────────────────
Total                                                   ≈ 185 000 → budget 250 000

// Helius
const response = await fetch(`https://mainnet.helius-rpc.com/?api-key=${apiKey}`, {
  method: "POST",
  body: JSON.stringify({
    jsonrpc: "2.0",
    id:      "fee-estimate",
    method:  "getPriorityFeeEstimate",
    params: [{
      accountKeys: [poolStatePubkey.toBase58()],
      options:     { priorityLevel: "High" },
    }],
  }),
});
const { result } = await response.json();
const microLamports = result.priorityFeeEstimate;

const fees = await connection.getRecentPrioritizationFees({
  lockedWritableAccounts: [poolStatePubkey],
});

// fees: Array<{ slot, prioritizationFee }>
// N emplacements récents ; par défaut ~150 emplacements.

const median = percentile(fees.map(f => f.prioritizationFee), 0.5);

cible par pool : taux d'atterrissage 80 % à <30s
si current_land_rate < 80 % : priorityFee += 10 %
si current_land_rate > 95 % : priorityFee -= 5 %

solana confirm <tx-sig> -v
# Cherchez « consumed N of M compute units » et quelle instruction a épuisé les ressources.

async function submitWithRetry(buildTx, maxAttempts = 5) {
  for (let attempt = 0; attempt < maxAttempts; attempt++) {
    const tx = await buildTx({
      priorityFee: basePriorityFee * Math.pow(1.5, attempt),
      blockhash:   (await connection.getLatestBlockhash()).blockhash,
    });

    try {
      const sig = await connection.sendRawTransaction(tx.serialize(), {
        skipPreflight: attempt > 0,  // skip after first try to save latency
      });

      const result = await connection.confirmTransaction(sig, "confirmed");
      if (result.value.err) {
        // Logic error; don't retry.
        throw result.value.err;
      }
      return sig;

    } catch (e) {
      if (isExpiredError(e)) continue;  // retry
      if (isRevertError(e)) throw e;    // don't retry; deterministic failure
      throw e;
    }
  }
  throw new Error("submit: exhausted retries");
}

CU moyen par tx :           ~250 000
Frais 50e percentile :      ~20 000 micro-lamports/CU
Coût par tx :               250_000 × 20_000 × 1e-6 = 5_000 lamports = 5e-6 SOL
Coût quotidien (1000 tx) :  5e-3 SOL ≈ $1 @ 200 $ SOL
Coût mensuel :              ~$30