policy: raise MAX_STANDARD_TX_SIGOPS to 16,000 for Bitcoin Computer

[reallyshadydev]

Summary

Raises the per-transaction policy sigops limit from 4,000 to 16,000 so Bitcoin Computer (and similar) transactions are no longer rejected with bad-txns-too-many-sigops.

Scope

• Policy only — no consensus change
• MAX_BLOCK_SIGOPS remains 20,000 (MAX_BLOCK_SIZE / 50)
• Older nodes stay more restrictive on relay; they do not fork

Context

Requested while integrating WOJAK into Bitcoin Computer:
bitcoin-computer/monorepo#456 (comment)

As noted there, the 4,000 limit is standardness, not consensus. Raising it is enough to relay a few BC transactions per block without a hard fork. Matches Bitcoin’s MAX_STANDARD_TX_SIGOPS_COST (16,000).

Test plan

• Build node (wojakcoind / wojakcoin-cli) with this change
• On regtest, broadcast high-sigop txs that would fail under the old 4,000 limit
• Confirm acceptance into mempool / rejection above 16,000
• Confirm block packing still respects unchanged 20,000 consensus limit

Regtest results

Built from branch raise-max-standard-tx-sigops, ran a local regtest node with -bytespersigop=0 so the density rule does not mask the per-tx sigops limit. Crafted 1-in / 1-out txs whose scriptPubKey is N × OP_CHECKSIG (legacy sigop count = N), signed via wallet, and submitted with sendrawtransaction.

Policy limit (MAX_STANDARD_TX_SIGOPS = 16,000)

Sigops	Expected	Result
100 (under old 4k)	accept	ACCEPTED cd615922…
5,000 (over old 4k, under 16k)	accept	ACCEPTED 2c053861…
16,000 (= new max)	accept	ACCEPTED 9e894d5d…
16,001 (over new max)	reject	REJECTED -26 bad-txns-too-many-sigops

All four cases PASS. The 5,000-sigop case is exactly the class of failure reported against Bitcoin Computer (bad-txns-too-many-sigops under the old 4,000 policy).

Consensus still 20k (MAX_BLOCK_SIGOPS unchanged)

Mempool held the three accepted txs (100 + 5,000 + 16,000 = 21,100 sigops total > 20,000 block budget). After generate 1:

• Block included: coinbase + 100-sigop + 5,000-sigop txs
• Left in mempool: 16,000-sigop tx (would exceed block sigops with the others)

So relay/mine policy is raised; block consensus packing still enforces the pre-existing 20,000 ceiling.