Add benchmark for async tree workloads (python#187)

Add a benchmark for testing async workloads, specifically an async tree workload that simulates simpler versions of a typical Instagram endpoint.  (See python/cpython#91121.)

doc/benchmarks.rst

@@ -57,6 +57,22 @@ depending on the Python version.
    them, and more generally to not modify them.
 
 
+async_tree
+----------
+
+Async workload benchmark, which calls ``asyncio.gather()`` on a tree (6 levels deep,
+6 branches per level) with the leaf nodes simulating some [potentially] async work
+(depending on the benchmark variant). Available variants:
+
+* ``async_tree``: no actual async work at any leaf node.
+* ``async_tree_io``: all leaf nodes simulate async IO workload (async sleep 50ms).
+* ``async_tree_memoization``: all leaf nodes simulate async IO workload with 90% of 
+  the data memoized.
+* ``async_tree_cpu_io_mixed``: half of the leaf nodes simulate CPU-bound workload
+  (``math.factorial(500)``) and the other half simulate the same workload as the 
+  ``async_tree_memoization`` variant.
+
+
 chameleon
 ---------
 

pyperformance/data-files/benchmarks/MANIFEST

@@ -2,6 +2,10 @@
 
 name	metafile
 2to3	<local>
+async_tree	<local>
+async_tree_cpu_io_mixed	<local:async_tree>
+async_tree_io	<local:async_tree>
+async_tree_memoization	<local:async_tree>
 chameleon	<local>
 chaos	<local>
 crypto_pyaes	<local>

pyperformance/data-files/benchmarks/bm_async_tree/bm_async_tree_cpu_io_mixed.toml

@@ -0,0 +1,4 @@
+[tool.pyperformance]
+name = "async_tree_cpu_io_mixed"
+extra_opts = ["cpu_io_mixed"]
+

pyperformance/data-files/benchmarks/bm_async_tree/bm_async_tree_io.toml

@@ -0,0 +1,4 @@
+[tool.pyperformance]
+name = "async_tree_io"
+extra_opts = ["io"]
+

pyperformance/data-files/benchmarks/bm_async_tree/bm_async_tree_memoization.toml

@@ -0,0 +1,4 @@
+[tool.pyperformance]
+name = "async_tree_memoization"
+extra_opts = ["memoization"]
+

pyperformance/data-files/benchmarks/bm_async_tree/pyproject.toml

@@ -0,0 +1,10 @@
+[project]
+name = "pyperformance_bm_async_tree"
+requires-python = ">=3.8"
+dependencies = ["pyperf"]
+urls = {repository = "https://github.com/python/pyperformance"}
+dynamic = ["version"]
+
+[tool.pyperformance]
+name = "async_tree"
+extra_opts = ["none"]

pyperformance/data-files/benchmarks/bm_async_tree/run_benchmark.py

@@ -0,0 +1,145 @@
+"""
+Benchmark for async tree workload, which calls asyncio.gather() on a tree
+(6 levels deep, 6 branches per level) with the leaf nodes simulating some
+(potentially) async work (depending on the benchmark variant). Benchmark
+variants include:
+
+1) "none": No actual async work in the async tree.
+2) "io": All leaf nodes simulate async IO workload (async sleep 50ms).
+3) "memoization": All leaf nodes simulate async IO workload with 90% of 
+                  the data memoized
+4) "cpu_io_mixed": Half of the leaf nodes simulate CPU-bound workload and 
+                   the other half simulate the same workload as the 
+                   "memoization" variant.
+"""
+
+
+import asyncio
+import math
+import random
+
+import pyperf
+
+
+NUM_RECURSE_LEVELS = 6
+NUM_RECURSE_BRANCHES = 6
+RANDOM_SEED = 0
+IO_SLEEP_TIME = 0.05
+MEMOIZABLE_PERCENTAGE = 90
+CPU_PROBABILITY = 0.5
+FACTORIAL_N = 500
+
+
+class AsyncTree:
+    def __init__(self):
+        self.cache = {}
+        # set to deterministic random, so that the results are reproducible
+        random.seed(RANDOM_SEED)
+
+    async def mock_io_call(self):
+        await asyncio.sleep(IO_SLEEP_TIME)
+
+    async def workload_func(self):
+        raise NotImplementedError(
+            "To be implemented by each variant's derived class."
+        )
+
+    async def recurse(self, recurse_level):
+        if recurse_level == 0:
+            await self.workload_func()
+            return
+
+        await asyncio.gather(
+            *[self.recurse(recurse_level - 1) for _ in range(NUM_RECURSE_BRANCHES)]
+        )
+
+    async def run(self):
+        await self.recurse(NUM_RECURSE_LEVELS)
+
+
+class NoneAsyncTree(AsyncTree):
+    async def workload_func(self):
+        return
+
+
+class IOAsyncTree(AsyncTree):
+    async def workload_func(self):
+        await self.mock_io_call()
+
+
+class MemoizationAsyncTree(AsyncTree):
+    async def workload_func(self):
+        # deterministic random, seed set in AsyncTree.__init__()
+        data = random.randint(1, 100)
+
+        if data <= MEMOIZABLE_PERCENTAGE:
+            if self.cache.get(data):
+                return data
+
+            self.cache[data] = True
+
+        await self.mock_io_call()
+        return data
+
+
+class CpuIoMixedAsyncTree(MemoizationAsyncTree):
+    async def workload_func(self):
+        # deterministic random, seed set in AsyncTree.__init__()
+        if random.random() < CPU_PROBABILITY:
+            # mock cpu-bound call
+            return math.factorial(FACTORIAL_N)
+        else:
+            return await MemoizationAsyncTree.workload_func(self)
+
+
+def add_metadata(runner):
+    runner.metadata["description"] = "Async tree workloads."
+    runner.metadata["async_tree_recurse_levels"] = NUM_RECURSE_LEVELS
+    runner.metadata["async_tree_recurse_branches"] = NUM_RECURSE_BRANCHES
+    runner.metadata["async_tree_random_seed"] = RANDOM_SEED
+    runner.metadata["async_tree_io_sleep_time"] = IO_SLEEP_TIME
+    runner.metadata["async_tree_memoizable_percentage"] = MEMOIZABLE_PERCENTAGE
+    runner.metadata["async_tree_cpu_probability"] = CPU_PROBABILITY
+    runner.metadata["async_tree_factorial_n"] = FACTORIAL_N
+
+
+def add_cmdline_args(cmd, args):
+    cmd.append(args.benchmark)
+
+
+def add_parser_args(parser):
+    parser.add_argument(
+        "benchmark",
+        choices=BENCHMARKS,
+        help="""\
+Determines which benchmark to run. Options:
+1) "none": No actual async work in the async tree.
+2) "io": All leaf nodes simulate async IO workload (async sleep 50ms).
+3) "memoization": All leaf nodes simulate async IO workload with 90% of 
+                  the data memoized
+4) "cpu_io_mixed": Half of the leaf nodes simulate CPU-bound workload and 
+                   the other half simulate the same workload as the 
+                   "memoization" variant.
+""",
+    )
+
+
+BENCHMARKS = {
+    "none": NoneAsyncTree,
+    "io": IOAsyncTree,
+    "memoization": MemoizationAsyncTree,
+    "cpu_io_mixed": CpuIoMixedAsyncTree,
+}
+
+
+if __name__ == "__main__":
+    runner = pyperf.Runner(add_cmdline_args=add_cmdline_args)
+    add_metadata(runner)
+    add_parser_args(runner.argparser)
+    args = runner.parse_args()
+    benchmark = args.benchmark
+
+    async_tree_class = BENCHMARKS[benchmark]
+    async_tree = async_tree_class()
+    runner.bench_async_func(f"async_tree_{benchmark}", async_tree.run)
+