hotfix: tasteful ctrl-c in parallel beam

.pre-commit-config.yaml

@@ -29,7 +29,7 @@ repos:
         pass_filenames: false
       - id: devicetests
         name: select GPU tests
-        entry: env GPU=1 PYTHONPATH="." pytest test/test_uops.py test/test_custom_function.py
+        entry: env GPU=1 PYTHONPATH="." pytest test/test_uops.py test/test_custom_function.py test/test_search.py
         language: system
         always_run: true
         pass_filenames: false

tinygrad/features/search.py

@@ -1,5 +1,5 @@
 from typing import Dict, List, cast, DefaultDict, Optional, Tuple, Callable
-import itertools, random, math, time, multiprocessing, traceback
+import itertools, random, math, time, multiprocessing, traceback, signal
 from tinygrad.lazy import vars_from_ast
 from tinygrad.device import Device, Compiled, Buffer
 from tinygrad.ops import MemBuffer
@@ -101,6 +101,9 @@ def time_program(dev:str, lib:bytes, global_size, local_size, var_vals, rawbufs,
     if early_stop is not None and early_stop < tms[-1]: break
   return tms
 
+# workers should ignore ctrl c
+def init_worker(): signal.signal(signal.SIGINT, signal.SIG_IGN)
+
 def beam_search(lin:Linearizer, rawbufs, amt:int, allow_test_size=True) -> Linearizer:
   key = {"ast": str(lin.ast), "amt": amt, "allow_test_size": allow_test_size, "device": Device.DEFAULT}
   if (val:=diskcache_get("beam_search", key)) is not None and not getenv("IGNORE_BEAM_CACHE") and CACHELEVEL >= 1:
@@ -112,32 +115,36 @@ def beam_search(lin:Linearizer, rawbufs, amt:int, allow_test_size=True) -> Linea
   seen_libs = set()
 
   default_parallel = 1 if Device.DEFAULT == "HIP" else 0
-  pool = multiprocessing.Pool(multiprocessing.cpu_count()) if getenv("PARALLEL", default_parallel) else None
+  pool = multiprocessing.Pool(multiprocessing.cpu_count(), init_worker) if getenv("PARALLEL", default_parallel) else None
 
-  var_vals = {k:(k.max+k.min)//2 for k in vars_from_ast(lin.ast)}
-  exiting, st = False, time.perf_counter()
-  dev = Device[Device.DEFAULT]
-  assert isinstance(dev, Compiled)
-  while not exiting:
-    acted_lins = flatten([get_linearizer_actions(lin, include_0=False).values() for lin,_ in beam]) if len(beam) else [lin]
-    timed_lins: List[Tuple[Linearizer, float]] = []
-    for i,proc in (pool.imap_unordered(try_compile_linearized_w_idx, enumerate(acted_lins)) if pool is not None else map(try_compile_linearized_w_idx, enumerate(acted_lins))):
-      if proc is None: continue
-      lib, global_size, local_size = proc
-      if lib in seen_libs: continue
-      seen_libs.add(lib)
-      tms = time_program(Device.DEFAULT, lib, global_size, local_size, var_vals, rawbufs, early_stop=beam[0][1]*3 if len(beam) else None)
-      timed_lins.append((acted_lins[i], min(tms)))
-      if DEBUG >= 2: print(f"\r{time.perf_counter() - st:7.2f}s: {timed_lins[-1][1]*1e6:12.2f} us       {len(timed_lins):4d}/{len(acted_lins):4d}         {timed_lins[-1][0].colored_shape()}\033[K", end="")
+  try:
+    var_vals = {k:(k.max+k.min)//2 for k in vars_from_ast(lin.ast)}
+    exiting, st = False, time.perf_counter()
+    dev = Device[Device.DEFAULT]
+    assert isinstance(dev, Compiled)
+    while not exiting:
+      acted_lins = flatten([get_linearizer_actions(lin, include_0=False).values() for lin,_ in beam]) if len(beam) else [lin]
+      timed_lins: List[Tuple[Linearizer, float]] = []
+      for i,proc in (pool.imap_unordered(try_compile_linearized_w_idx, enumerate(acted_lins)) if pool is not None else map(try_compile_linearized_w_idx, enumerate(acted_lins))):
+        if proc is None: continue
+        lib, global_size, local_size = proc
+        if lib in seen_libs: continue
+        seen_libs.add(lib)
+        tms = time_program(Device.DEFAULT, lib, global_size, local_size, var_vals, rawbufs, early_stop=beam[0][1]*3 if len(beam) else None)
+        timed_lins.append((acted_lins[i], min(tms)))
+        if DEBUG >= 2: print(f"\r{time.perf_counter() - st:7.2f}s: {timed_lins[-1][1]*1e6:12.2f} us       {len(timed_lins):4d}/{len(acted_lins):4d}         {timed_lins[-1][0].colored_shape()}\033[K", end="")
 
-    # done
-    opts = sorted(timed_lins, key=lambda x: x[1])
-    exiting = len(opts) == 0 or (len(beam) > 0 and beam[0][1] <= opts[0][1])
-    if not exiting: beam = opts[:amt]
-    assert len(beam) > 0, "no BEAM items succeeded?!?"
-    if DEBUG >= 2: print(f"\r{time.perf_counter() - st:7.2f}s:", colored(f"{beam[0][1]*1e6:12.2f} us", "green" if exiting else None), f"from {len(acted_lins):3d} -> {len(opts):3d} actions\033[K", beam[0][0].colored_shape())
+      # done
+      opts = sorted(timed_lins, key=lambda x: x[1])
+      exiting = len(opts) == 0 or (len(beam) > 0 and beam[0][1] <= opts[0][1])
+      if not exiting: beam = opts[:amt]
+      assert len(beam) > 0, "no BEAM items succeeded?!?"
+      if DEBUG >= 2: print(f"\r{time.perf_counter() - st:7.2f}s:", colored(f"{beam[0][1]*1e6:12.2f} us", "green" if exiting else None), f"from {len(acted_lins):3d} -> {len(opts):3d} actions\033[K", beam[0][0].colored_shape())
+    if pool is not None: pool.close()    # the pool is closed
+  except KeyboardInterrupt as e:
+    if pool is not None: pool.terminate()
+    raise e
 
-  if pool is not None: pool.close()    # the pool is closed
   if CACHELEVEL >= 1: diskcache_put("beam_search", key, beam[0][0].applied_opts)
   if DEBUG >= 3: print(beam[0][0].applied_opts)
   return beam[0][0]