tpcc: reuse fixed transaction inputs across retry attempts#1
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Generate user input once per business transaction and cache it in TTransactionContext so retry loops do not re-roll RandomNumber and execute a different business transaction. Fixes ydb-platform#1 Co-authored-by: Maksim Zinal <zinal@ydb.tech>
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Fixes ydb-platform#1
Problem
The retry loop in
terminal.cppre-invokes the entire transaction coroutine on rollback. Random user inputs (district, customer, items, etc.) are generated inside transaction functions, so each retry effectively executes a different business transaction.Solution
Mirror the approach from ydb-platform/ydb#47316:
FixedInputstoTTransactionContextand aFixedTransactionInputs<T>()helper that lazily generates and caches inputs.Context.FixedInputsbefore each new business transaction (outside the retry loop).NewOrder,Delivery,OrderStatus,Payment,StockLevel) into a localTInputsstruct cached viaFixedTransactionInputs.This ensures retries reuse the same user input while new business transactions still get fresh random values.