Revert "refactor: retire sketch-core mirror (#307)"

Cargo.toml

@@ -1,6 +1,7 @@
 [workspace]
 resolver = "2"
 members = [
+    "asap-common/sketch-core",
     "asap-common/dependencies/rs/promql_utilities",
     "asap-common/dependencies/rs/sql_utilities",
     "asap-common/dependencies/rs/elastic_dsl_utilities",
@@ -31,6 +32,7 @@ promql-parser = "0.5.0"
 tokio = { version = "1.0", features = ["full"] }
 
 # Internal crates
+sketch-core = { path = "asap-common/sketch-core" }
 promql_utilities = { path = "asap-common/dependencies/rs/promql_utilities" }
 sql_utilities = { path = "asap-common/dependencies/rs/sql_utilities" }
 asap_types = { path = "asap-common/dependencies/rs/asap_types" }

asap-common/sketch-core/Cargo.toml

@@ -0,0 +1,16 @@
+[package]
+name = "sketch-core"
+version.workspace = true
+edition.workspace = true
+
+[dependencies]
+serde.workspace = true
+# sketch-core-specific, keep pinned
+rmp-serde = "1.1"
+xxhash-rust = { version = "0.8", features = ["xxh32"] }
+dsrs = { git = "https://github.com/ProjectASAP/datasketches-rs", rev = "d748ec75c80fff21f7b24897244dd1c895df2e9a" }
+asap_sketchlib = { git = "https://github.com/ProjectASAP/asap_sketchlib" }
+clap = { version = "4.0", features = ["derive"] }
+
+[dev-dependencies]
+ctor = "0.2"

asap-common/sketch-core/report.md

@@ -0,0 +1,125 @@
+# Report
+
+Compares the **legacy** sketch implementations in `sketch-core` vs the **asap_sketchlib** backends (Count-Min Sketch, Count-Min-With-Heap, KLL, HydraKLL).
+
+## Fidelity harness
+
+The fidelity binary selects backends via CLI flags (`--cms-impl`, `--kll-impl`, `--cmwh-impl`).
+
+| Goal                     | Command                                                                                                      |
+|--------------------------|--------------------------------------------------------------------------------------------------------------|
+| Default (all sketchlib)  | `cargo run -p sketch-core --bin sketchlib_fidelity`                                                          |
+| All legacy               | `cargo run -p sketch-core --bin sketchlib_fidelity -- --cms-impl legacy --kll-impl legacy --cmwh-impl legacy` |
+| Legacy KLL only        | `cargo run -p sketch-core --bin sketchlib_fidelity -- --cms-impl sketchlib --kll-impl legacy --cmwh-impl sketchlib` |
+| CMS sketchlib only       | `cargo run -p sketch-core --bin sketchlib_fidelity -- --cms-impl sketchlib`                                   |
+| CMS legacy only          | `cargo run -p sketch-core --bin sketchlib_fidelity -- --cms-impl legacy`                                     |
+
+## Unit tests
+
+Unit tests always run with **legacy** backends enabled (the test ctor calls
+`force_legacy_mode_for_tests()`), so you only need:
+
+```bash
+cargo test -p sketch-core
+```
+
+## Results
+
+### CountMinSketch (accuracy vs exact counts)
+
+#### depth=3
+
+| width | n      | domain | Mode           | Pearson corr   | MAPE (%) | RMSE (%) |
+|-------|--------|--------|----------------|----------------|----------|----------|
+| 1024  | 100000 | 1000   | Legacy         | 0.9998451189   | 24.48    | 52.76    |
+| 1024  | 100000 | 1000   | asap_sketchlib | 0.9998387103   | 24.36    | 54.11    |
+
+#### depth=5
+
+| width | n      | domain | Mode           | Pearson corr   | MAPE (%) | RMSE (%) |
+|-------|--------|--------|----------------|----------------|----------|----------|
+| 2048  | 200000 | 2000   | Legacy         | 0.9999733814   | 8.75     | 29.94    |
+| 2048  | 200000 | 2000   | asap_sketchlib | 0.9999744627   | 8.37     | 28.84    |
+| 2048  | 50000  | 500    | Legacy         | 1.0000000000   | 0.00     | 0.00     |
+| 2048  | 50000  | 500    | asap_sketchlib | 1.0000000000   | 0.00     | 0.00     |
+
+#### depth=7
+
+| width | n      | domain | Mode           | Pearson corr   | MAPE (%) | RMSE (%) |
+|-------|--------|--------|----------------|----------------|----------|----------|
+| 4096  | 200000 | 2000   | Legacy         | 0.9999993694   | 0.20     | 3.69     |
+| 4096  | 200000 | 2000   | asap_sketchlib | 0.9999993499   | 0.21     | 4.27     |
+
+---
+
+### CountMinSketchWithHeap (top-k + CMS accuracy on exact top-k)
+
+The heap is maintained by local updates; recall is measured against the **true** top-k at the end of the stream.
+
+#### depth=3
+
+| width | n      | domain | heap_size | Mode           | Top-k recall | Pearson (top-k) | MAPE (%) | RMSE (%) |
+|-------|--------|--------|-----------|----------------|--------------|-----------------|----------|----------|
+| 1024  | 100000 | 1000   | 10        | Legacy         | 0.40         | 0.9571          | 0.174    | 0.319    |
+| 1024  | 100000 | 1000   | 10        | asap_sketchlib | 0.80         | 1.0000          | 0.000    | 0.000    |
+
+#### depth=5
+
+| width | n      | domain | heap_size | Mode           | Top-k recall | Pearson (top-k) | MAPE (%) | RMSE (%) |
+|-------|--------|--------|-----------|----------------|--------------|-----------------|----------|----------|
+| 2048  | 200000 | 2000   | 20        | Legacy         | 0.60         | 0.9964          | 0.045    | 0.101    |
+| 2048  | 200000 | 2000   | 20        | asap_sketchlib | 1.00         | 0.9982          | 0.021    | 0.067    |
+| 2048  | 200000 | 2000   | 50        | Legacy         | 0.40         | 0.9999983       | 5.60     | 16.49    |
+| 2048  | 200000 | 2000   | 50        | asap_sketchlib | 0.48         | 0.9999990       | 3.90     | 12.95    |
+
+---
+
+### KllSketch (quantiles, absolute rank error)
+
+For each quantile \(q\), we compute the sketch estimate `est_value`, then:
+`abs_rank_error = |rank_fraction(exact_sorted_values, est_value) - q|`.
+
+#### k=20
+
+| n_updates | Mode           | q=0.5   | q=0.9   | q=0.99  |
+|-----------|----------------|---------|---------|---------|
+| 200000    | Legacy         | 0.0104  | 0.0145  | 0.0028  |
+| 200000    | asap_sketchlib | 0.0275  | 0.0470  | 0.0061  |
+| 50000     | Legacy         | 0.0131  | 0.0091  | 0.0054  |
+| 50000     | asap_sketchlib | 0.0110  | 0.0116  | 0.0031  |
+
+#### k=50
+
+| n_updates | Mode           | q=0.5   | q=0.9   | q=0.99  |
+|-----------|----------------|---------|---------|---------|
+| 200000    | Legacy         | 0.0013  | 0.0021  | 0.0012  |
+| 200000    | asap_sketchlib | 0.0101  | 0.0044  | 0.0074  |
+
+#### k=200
+
+| n_updates | Mode           | q=0.5   | q=0.9   | q=0.99  |
+|-----------|----------------|---------|---------|---------|
+| 200000    | Legacy         | 0.0021  | 0.0036  | 0.0000  |
+| 200000    | asap_sketchlib | 0.0015  | 0.0001  | 0.0002  |
+
+---
+
+### HydraKllSketch (per-key quantiles, mean/max absolute rank error across 50 keys)
+
+#### rows=2, cols=64
+
+| k   | n      | domain | Mode           | q=0.5 (mean / max) | q=0.9 (mean / max) |
+|-----|--------|--------|----------------|--------------------|--------------------|
+| 20  | 200000 | 200    | Legacy         | 0.0170 / 0.0546    | 0.0165 / 0.0452    |
+| 20  | 200000 | 200    | asap_sketchlib | 0.0254 / 0.0629    | 0.0546 / 0.0942    |
+
+#### rows=3, cols=128
+
+| k   | n      | domain | Mode           | q=0.5 (mean / max) | q=0.9 (mean / max) |
+|-----|--------|--------|----------------|--------------------|--------------------|
+| 20  | 200000 | 200    | Legacy         | 0.0166 / 0.0591    | 0.0114 / 0.0304    |
+| 20  | 200000 | 200    | asap_sketchlib | 0.0216 / 0.0534    | 0.0238 / 0.1087    |
+| 50  | 200000 | 200    | Legacy         | 0.0099 / 0.0352    | 0.0087 / 0.0330    |
+| 50  | 200000 | 200    | asap_sketchlib | 0.0119 / 0.0458    | 0.0119 / 0.0296    |
+| 20  | 100000 | 100    | Legacy         | 0.0141 / 0.0574    | 0.0149 / 0.0471    |
+| 20  | 100000 | 100    | asap_sketchlib | 0.0202 / 0.0621    | 0.0287 / 0.0779    |