Add benchmark vs tiktoken (#1582)

* Adding a simple tiktoken benchmark.

* Adding 1 large fused document case.

bindings/python/benches/test_tiktoken.py

@@ -0,0 +1,117 @@
+import os
+import time
+import argparse
+from datasets import load_dataset
+from tiktoken.load import load_tiktoken_bpe
+import tiktoken
+from tokenizers import Tokenizer
+from huggingface_hub import hf_hub_download
+from typing import Tuple, List
+
+MODEL_ID = "meta-llama/Meta-Llama-3.1-8B"
+DATASET = "facebook/xnli"
+DATASET_CONFIG = "all_languages"
+DEFAULT_THREADS = [2**i for i in range(8) if 2**i <= os.cpu_count()]
+
+
+def format_byte_size(num_bytes: int) -> Tuple[str, str]:
+    """Convert bytes to a human-readable format (KB, MB, GB)."""
+    num_bytes_f = float(num_bytes)
+    for unit in ["B", "KB", "MB", "GB", "TB"]:
+        if num_bytes_f < 1024:
+            return f"{num_bytes_f:.2f} {unit}", unit
+        num_bytes_f /= 1024
+    return f"{num_bytes_f:.2f} PB", "PB"
+
+
+def benchmark_batch(model: str, documents: list[str]) -> None:
+    num_threads = int(os.environ["RAYON_NUM_THREADS"])
+    num_bytes = sum(map(len, map(str.encode, documents)))
+    readable_size, unit = format_byte_size(num_bytes)
+    print(f"==============")
+    print(f"num_threads: {num_threads}, data size: {readable_size}, documents: {len(documents)}")
+    filename = hf_hub_download(MODEL_ID, "original/tokenizer.model")
+    mergeable_ranks = load_tiktoken_bpe(filename)
+    pat_str = r"(?i:'s|'t|'re|'ve|'m|'ll|'d)|[^\r\n\p{L}\p{N}]?\p{L}+|\p{N}{1,3}| ?[^\s\p{L}\p{N}]+[\r\n]*|\s*[\r\n]+|\s+(?!\S)|\s+"
+    num_reserved_special_tokens = 256
+    special_tokens = [
+            "<|begin_of_text|>",
+            "<|end_of_text|>",
+            "<|reserved_special_token_0|>",
+            "<|reserved_special_token_1|>",
+            "<|reserved_special_token_2|>",
+            "<|reserved_special_token_3|>",
+            "<|start_header_id|>",
+            "<|end_header_id|>",
+            "<|reserved_special_token_4|>",
+            "<|eot_id|>",  # end of turn
+        ] + [
+            f"<|reserved_special_token_{i}|>"
+            for i in range(5, num_reserved_special_tokens - 5)
+        ]
+    num_base_tokens = len(mergeable_ranks)
+    special_tokens = {
+        token: num_base_tokens + i for i, token in enumerate(special_tokens)
+    }
+    enc = tiktoken.Encoding(
+            name=model,
+            pat_str=pat_str,
+            mergeable_ranks=mergeable_ranks,
+            special_tokens=special_tokens,
+        )
+    enc.encode("warmup")
+
+    start = time.perf_counter_ns()
+    enc.encode_ordinary_batch(documents, num_threads=num_threads)
+    end = time.perf_counter_ns()
+
+    readable_size, unit = format_byte_size(num_bytes / (end - start) * 1e9)
+    print(f"tiktoken \t{readable_size}  / s")
+
+    hf_enc = Tokenizer.from_pretrained(model)
+    hf_enc.encode("warmup")
+
+    start = time.perf_counter_ns()
+    hf_enc.encode_batch(documents)
+    end = time.perf_counter_ns()
+    readable_size, unit = format_byte_size(num_bytes / (end - start) * 1e9)
+    print(f"huggingface \t{readable_size} / s")
+
+
+def test(model: str, dataset: str, dataset_config: str, threads: List[int]):
+    dataset_xnli = load_dataset(dataset, dataset_config)
+
+    input_lengths = [(10, False), (10_000, False), (10_000, True)]  # Example input lengths
+
+    for num_threads in threads:
+        os.environ["RAYON_NUM_THREADS"] = str(num_threads)
+        os.environ["TOKENIZER_PARALLELISM"] = str(num_threads)
+        os.environ["RAYON_RS_NUM_THREADS"] = str(num_threads)
+        for length, fuse in input_lengths:
+            documents = []
+            for i, item in enumerate(dataset_xnli["train"]):
+                documents.append("".join(item["premise"].values()))
+                if i >= length:
+                    break
+            if fuse:
+                documents=["".join(documents)]
+            benchmark_batch(model, documents)
+
+
+def main():
+
+    parser = argparse.ArgumentParser(
+                    prog='bench_tokenizer',
+                    description='Getting a feel for speed when tokenizing',
+    )
+    parser.add_argument('-m', '--model', default=MODEL_ID, type=str)
+    parser.add_argument('-d', '--dataset', default=DATASET, type=str)
+    parser.add_argument('-ds', '--dataset-config', default=DATASET_CONFIG, type=str)
+    parser.add_argument('-t', '--threads', nargs='+', default=DEFAULT_THREADS, type=int)
+    args = parser.parse_args()
+    test(args.model, args.dataset, args.dataset_config, args.threads)
+
+
+# Call the function to run the benchmark
+if __name__ == "__main__":
+    main()