feat(asap-tools): run generated2 PromQL workloads on ClickHouse

[milindsrivastava1997]

Summary

Runs the generated2 workloads (ASAPQuery vs Prometheus/VictoriaMetrics) as a standalone ClickHouse baseline, using SQL with the same semantics as Prometheus 2.53, instead of going through ASAPQuery's SQL support.

• datasets/fake_metric/generate_data.py + init.sql: fake_exporter-equivalent data (zipf, valuescale 10000, 3 labels x 20 values, counter with one shared accumulator per instance, 1s scrapes). --num-instances sets the scale (1 = 1x, 10 = 10x).
• datasets/fake_metric/generate_workloads.py: maps the PromQL shapes used in generated2 to templated ClickHouse SQL and writes one baseline-only experiment_run_clickhouse.py config per workload (to the gitignored config/experiment_type/generated2_clickhouse/). Unknown shapes raise an error.
  • Instant vectors read (T-1s, T]; range vectors [d] read (T-d, T].
  • Quantiles use quantileExactInclusive, which interpolates the same way as Prometheus quantile.
  • rate/increase reproduce extrapolatedRate from Prometheus 2.53. There is no counter-reset handling because the fake counters never reset.
• prometheus-client: new client_options.simulated_start_time. When set, {{ end_time }} advances on a clock anchored at the start of the bulk-loaded data rather than the wall clock. Pacing between repetitions is unchanged. A later paced-feeder run can drop this option and keep the same SQL.

Testing

• Ran all 27 distinct generated SQL statements in clickhouse-local and compared them against a separate Python implementation of the PromQL semantics. Every statement matched at 3 evaluation times, which together cover both rate-extrapolation branches, the zero clamp, and empty windows.
• Checked with a stubbed client that simulated_start_time together with starting_delay, repetition_delay_ms and query_time_offset renders the expected end_time.
• Ran config 1 at 1x end to end on CloudLab: all 5775 queries returned complete results (20 rows per group-1 query, 8000 per group-2 query).

🤖 Generated with Claude Code