From aaeb8582f494c9e2648302c48f864dee0d710457 Mon Sep 17 00:00:00 2001
From: Hamel Husain <hamel.husain@gmail.com>
Date: Fri, 11 Oct 2024 21:09:34 -0700
Subject: [PATCH] clean up parallel async

---
 fastcore/parallel.py   |  5 +----
 nbs/03a_parallel.ipynb | 34 ++++++++++++++++++++++------------
 2 files changed, 23 insertions(+), 16 deletions(-)

diff --git a/fastcore/parallel.py b/fastcore/parallel.py
index 683aa071..fbaa5e92 100644
--- a/fastcore/parallel.py
+++ b/fastcore/parallel.py
@@ -141,13 +141,11 @@ def _add_one(x, a=1):
     return x+a
 
 # %% ../nbs/03a_parallel.ipynb
-async def parallel_async(f, items, *args, n_workers=16, total=None,
+async def parallel_async(f, items, *args, n_workers=16,
                          timeout=None, chunksize=1, on_exc=print, **kwargs):
     "Applies `f` to `items` in parallel using asyncio and a semaphore to limit concurrency."
     import asyncio
-    if n_workers is None: n_workers = defaults.cpus
     semaphore = asyncio.Semaphore(n_workers)
-    results = []
 
     async def limited_task(item):
         coro = f(item, *args, **kwargs) if asyncio.iscoroutinefunction(f) else asyncio.to_thread(f, item, *args, **kwargs)
@@ -155,7 +153,6 @@ async def limited_task(item):
             return await asyncio.wait_for(coro, timeout) if timeout else await coro
 
     tasks = [limited_task(item) for item in items]
-    if total is None: total = len(items)
     return asyncio.gather(*tasks)
 
 # %% ../nbs/03a_parallel.ipynb
diff --git a/nbs/03a_parallel.ipynb b/nbs/03a_parallel.ipynb
index b3c9e53f..d18a7a51 100644
--- a/nbs/03a_parallel.ipynb
+++ b/nbs/03a_parallel.ipynb
@@ -363,7 +363,7 @@
        "\n",
        ">      ProcessPoolExecutor (max_workers=8, on_exc=<built-in function print>,\n",
        ">                           pause=0, mp_context=None, initializer=None,\n",
-       ">                           initargs=(), max_tasks_per_child=None)\n",
+       ">                           initargs=())\n",
        "\n",
        "*Same as Python's ProcessPoolExecutor, except can pass `max_workers==0` for serial execution*"
       ],
@@ -376,7 +376,7 @@
        "\n",
        ">      ProcessPoolExecutor (max_workers=8, on_exc=<built-in function print>,\n",
        ">                           pause=0, mp_context=None, initializer=None,\n",
-       ">                           initargs=(), max_tasks_per_child=None)\n",
+       ">                           initargs=())\n",
        "\n",
        "*Same as Python's ProcessPoolExecutor, except can pass `max_workers==0` for serial execution*"
       ]
@@ -479,11 +479,11 @@
      "name": "stdout",
      "output_type": "stream",
      "text": [
-      "0 2024-10-12 13:30:21.217649\n",
-      "1 2024-10-12 13:30:21.469191\n",
-      "2 2024-10-12 13:30:21.721034\n",
-      "3 2024-10-12 13:30:21.972793\n",
-      "4 2024-10-12 13:30:22.223159\n"
+      "0 2024-10-11 21:08:04.678835\n",
+      "1 2024-10-11 21:08:04.930711\n",
+      "2 2024-10-11 21:08:05.181549\n",
+      "3 2024-10-11 21:08:05.435812\n",
+      "4 2024-10-11 21:08:05.687301\n"
      ]
     }
    ],
@@ -527,13 +527,11 @@
    "outputs": [],
    "source": [
     "#|export\n",
-    "async def parallel_async(f, items, *args, n_workers=16, total=None,\n",
+    "async def parallel_async(f, items, *args, n_workers=16,\n",
     "                         timeout=None, chunksize=1, on_exc=print, **kwargs):\n",
     "    \"Applies `f` to `items` in parallel using asyncio and a semaphore to limit concurrency.\"\n",
     "    import asyncio\n",
-    "    if n_workers is None: n_workers = defaults.cpus\n",
     "    semaphore = asyncio.Semaphore(n_workers)\n",
-    "    results = []\n",
     "\n",
     "    async def limited_task(item):\n",
     "        coro = f(item, *args, **kwargs) if asyncio.iscoroutinefunction(f) else asyncio.to_thread(f, item, *args, **kwargs)\n",
@@ -541,7 +539,6 @@
     "            return await asyncio.wait_for(coro, timeout) if timeout else await coro\n",
     "\n",
     "    tasks = [limited_task(item) for item in items]\n",
-    "    if total is None: total = len(items)\n",
     "    return asyncio.gather(*tasks)"
    ]
   },
@@ -558,7 +555,20 @@
    "cell_type": "code",
    "execution_count": null,
    "metadata": {},
-   "outputs": [],
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "2 2024-10-11 21:08:23.196473 0.28277557322761593\n",
+      "1 2024-10-11 21:08:23.258949 0.3449957623467014\n",
+      "0 2024-10-11 21:08:23.341502 0.4269314183522479\n",
+      "5 2024-10-11 21:08:23.665180 0.3214516296250627\n",
+      "3 2024-10-11 21:08:23.814849 0.6164311736352199\n",
+      "4 2024-10-11 21:08:23.864115 0.6032399559625771\n"
+     ]
+    }
+   ],
    "source": [
     "async def print_time_async(i): \n",
     "    wait = random.random()\n",