Omit possible high-sigop txs from block health score

backend/src/api/audit.ts

@@ -6,14 +6,15 @@ const PROPAGATION_MARGIN = 180; // in seconds, time since a transaction is first
 
 class Audit {
   auditBlock(transactions: TransactionExtended[], projectedBlocks: MempoolBlockWithTransactions[], mempool: { [txId: string]: TransactionExtended })
-   : { censored: string[], added: string[], fresh: string[], score: number, similarity: number } {
+   : { censored: string[], added: string[], fresh: string[], sigop: string[], score: number, similarity: number } {
     if (!projectedBlocks?.[0]?.transactionIds || !mempool) {
-      return { censored: [], added: [], fresh: [], score: 0, similarity: 1 };
+      return { censored: [], added: [], fresh: [], sigop: [], score: 0, similarity: 1 };
     }
 
     const matches: string[] = []; // present in both mined block and template
     const added: string[] = []; // present in mined block, not in template
     const fresh: string[] = []; // missing, but firstSeen within PROPAGATION_MARGIN
+    const sigop: string[] = []; // missing, but possibly has an adjusted vsize due to high sigop count
     const isCensored = {}; // missing, without excuse
     const isDisplaced = {};
     let displacedWeight = 0;
@@ -37,6 +38,8 @@ class Audit {
         // tx is recent, may have reached the miner too late for inclusion
         if (mempool[txid]?.firstSeen != null && (now - (mempool[txid]?.firstSeen || 0)) <= PROPAGATION_MARGIN) {
           fresh.push(txid);
+        } else if (this.isPossibleHighSigop(mempool[txid])) {
+          sigop.push(txid);
         } else {
           isCensored[txid] = true;
         }
@@ -137,10 +140,19 @@ class Audit {
       censored: Object.keys(isCensored),
       added,
       fresh,
+      sigop,
       score,
       similarity,
     };
   }
+
+  // Detect transactions with a possibly adjusted vsize due to high sigop count
+  // very rough heuristic based on number of OP_CHECKMULTISIG outputs
+  // will miss cases with other sources of sigops
+  isPossibleHighSigop(tx: TransactionExtended): boolean {
+    const numBareMultisig = tx.vout.reduce((count, vout) => count + (vout.scriptpubkey_asm.includes('OP_CHECKMULTISIG') ? 1 : 0), 0);
+    return (numBareMultisig * 400) > tx.vsize;
+  }
 }
 
 export default new Audit();

backend/src/api/database-migration.ts

@@ -7,7 +7,7 @@ import cpfpRepository from '../repositories/CpfpRepository';
 import { RowDataPacket } from 'mysql2';
 
 class DatabaseMigration {
-  private static currentVersion = 59;
+  private static currentVersion = 60;
   private queryTimeout = 3600_000;
   private statisticsAddedIndexed = false;
   private uniqueLogs: string[] = [];
@@ -516,6 +516,11 @@ class DatabaseMigration {
       // https://github.com/mempool/mempool/issues/3360
       await this.$executeQuery(`TRUNCATE prices`);
     }
+
+    if (databaseSchemaVersion < 60 && isBitcoin === true) {
+      await this.$executeQuery('ALTER TABLE `blocks_audits` ADD sigop_txs JSON DEFAULT "[]"');
+      await this.updateToSchemaVersion(60);
+    }
   }
 
   /**

backend/src/api/websocket-handler.ts

@@ -557,7 +557,7 @@ class WebsocketHandler {
       }
 
       if (Common.indexingEnabled() && memPool.isInSync()) {
-        const { censored, added, fresh, score, similarity } = Audit.auditBlock(transactions, projectedBlocks, auditMempool);
+        const { censored, added, fresh, sigop, score, similarity } = Audit.auditBlock(transactions, projectedBlocks, auditMempool);
         const matchRate = Math.round(score * 100 * 100) / 100;
 
         const stripped = projectedBlocks[0]?.transactions ? projectedBlocks[0].transactions.map((tx) => {
@@ -584,6 +584,7 @@ class WebsocketHandler {
           addedTxs: added,
           missingTxs: censored,
           freshTxs: fresh,
+          sigopTxs: sigop,
           matchRate: matchRate,
         });