Struct BlockSessionContext 

pub struct BlockSessionContext {

    pub block: Arc<Block>,
    pub prevout_values_buffer: Arc<Vec<i64>>,
    pub script_pubkey_indices_buffer: Arc<Vec<(usize, usize)>>,
    pub script_pubkey_buffer: Arc<Vec<u8>>,
    pub witness_buffer: Arc<Vec<Vec<Witness>>>,
    pub tx_contexts: Arc<Vec<TxScriptContext>>,
    pub ecdsa_sub_counters: Arc<Vec<AtomicUsize>>,
    pub schnorr_collector: Option<Arc<SchnorrSignatureCollector>>,
    pub height: Natural,
    pub median_time_past: Option<u64>,
    pub network: Network,
    pub activation: ForkActivationTable,
    pub results: Arc<SegQueue<Vec<(usize, bool)>>>,
    pub precomputed_sighashes: Arc<Vec<Option<[u8; 32]>>>,
    pub precomputed_p2pkh_hashes: Arc<Vec<Option<[u8; 20]>>>,
}

Session context for one block; set at start_session, used by workers until complete. When schnorr_collector is None, verify in-place (no batch collection). TxScriptContext stored in Arc to avoid cloning full context per check (workers get Arc::clone). Block-level buffers are immutable (Arc<Vec<…>>) — no locks during worker execution.

Fields

block: Arc<Block>

prevout_values_buffer: Arc<Vec<i64>>

Block-level buffer for all prevout values; TxScriptContext.prevout_values_range indexes into this.

script_pubkey_indices_buffer: Arc<Vec<(usize, usize)>>

Block-level buffer for (start, len) pairs into script_pubkey_buffer; TxScriptContext.script_pubkey_indices_range indexes into this.

script_pubkey_buffer: Arc<Vec<u8>>

Block-level buffer for all prevout script_pubkeys; (start, len) from script_pubkey_indices_buffer index into this.

witness_buffer: Arc<Vec<Vec<Witness>>>

Block-level witness data; workers index via session.witness_buffer[ctx.tx_index][input_idx].

tx_contexts: Arc<Vec<TxScriptContext>>

ecdsa_sub_counters: Arc<Vec<AtomicUsize>>

schnorr_collector: Option<Arc<SchnorrSignatureCollector>>

height: Natural

median_time_past: Option<u64>

network: Network

activation: ForkActivationTable

Fork heights for this validation session (same table as BlockValidationContext::activation).

results: Arc<SegQueue<Vec<(usize, bool)>>>

Lock-free: workers push batch_results; master drains at complete(). Reduces Mutex contention.

precomputed_sighashes: Arc<Vec<Option<[u8; 32]>>>

Precomputed sighashes for P2PKH inputs, indexed by ecdsa_index_base + input_idx. None = not precomputed (worker computes on demand).

precomputed_p2pkh_hashes: Arc<Vec<Option<[u8; 20]>>>

Precomputed HASH160(pubkey) for P2PKH inputs, indexed same as precomputed_sighashes.