Checking health of information technology infrastructure based on log data, in one aspect, may collect log data non-intrusively from a production system, said log data at least associated with transactions occurring in the production system and resource utilization of the production system, may normalize said log data into a plurality of log data types, may perform data regression analysis using said plurality of log data types to estimate resources consumed by each of said transactions and throughput of each of said transactions, and may use a queuing model to predict performance of the information technology infrastructure under various workloads.