accurate num.cores detection

bin/up2k.py

@@ -929,7 +929,7 @@ def main():
     if not VT100:
         os.system("rem")  # enables colors
 
-    cores = os.cpu_count() if hasattr(os, "cpu_count") else 4
+    cores = (os.cpu_count() if hasattr(os, "cpu_count") else 0) or 2
     hcores = min(cores, 3)  # 4% faster than 4+ on py3.9 @ r5-4500U
 
     # fmt: off

copyparty/__init__.py

@@ -33,6 +33,11 @@ ANYWIN = WINDOWS or sys.platform in ["msys", "cygwin"]
 
 MACOS = platform.system() == "Darwin"
 
+try:
+    CORES = len(os.sched_getaffinity(0))
+except:
+    CORES = (os.cpu_count() if hasattr(os, "cpu_count") else 0) or 2
+
 
 def get_unixdir() -> str:
     paths: list[tuple[Callable[..., str], str]] = [

copyparty/__main__.py

@@ -20,7 +20,7 @@ import time
 import traceback
 from textwrap import dedent
 
-from .__init__ import ANYWIN, PY2, VT100, WINDOWS, E, unicode
+from .__init__ import ANYWIN, PY2, VT100, WINDOWS, E, unicode, CORES
 from .__version__ import CODENAME, S_BUILD_DT, S_VERSION
 from .authsrv import re_vol
 from .svchub import SvcHub
@@ -335,8 +335,7 @@ def run_argparse(argv: list[str], formatter: Any, retry: bool) -> argparse.Names
     except:
         fk_salt = "hunter2"
 
-    cores = (os.cpu_count() if hasattr(os, "cpu_count") else 0) or 4
-    hcores = min(cores, 3)  # 4% faster than 4+ on py3.9 @ r5-4500U
+    hcores = min(CORES, 3)  # 4% faster than 4+ on py3.9 @ r5-4500U
 
     sects = [
         [
@@ -576,7 +575,7 @@ def run_argparse(argv: list[str], formatter: Any, retry: bool) -> argparse.Names
     ap2.add_argument("--no-athumb", action="store_true", help="disable audio thumbnails (spectrograms)")
     ap2.add_argument("--no-vthumb", action="store_true", help="disable video thumbnails")
     ap2.add_argument("--th-size", metavar="WxH", default="320x256", help="thumbnail res")
-    ap2.add_argument("--th-mt", metavar="CORES", type=int, default=cores, help="num cpu cores to use for generating thumbnails")
+    ap2.add_argument("--th-mt", metavar="CORES", type=int, default=CORES, help="num cpu cores to use for generating thumbnails")
     ap2.add_argument("--th-convt", metavar="SEC", type=int, default=60, help="conversion timeout in seconds")
     ap2.add_argument("--th-no-crop", action="store_true", help="dynamic height; show full image")
     ap2.add_argument("--th-dec", metavar="LIBS", default="vips,pil,ff", help="image decoders, in order of preference")
@@ -626,7 +625,7 @@ def run_argparse(argv: list[str], formatter: Any, retry: bool) -> argparse.Names
     ap2.add_argument("-e2tsr", action="store_true", help="delete all metadata from DB and do a full rescan; sets -e2ts")
     ap2.add_argument("--no-mutagen", action="store_true", help="use FFprobe for tags instead; will catch more tags")
     ap2.add_argument("--no-mtag-ff", action="store_true", help="never use FFprobe as tag reader; is probably safer")
-    ap2.add_argument("--mtag-mt", metavar="CORES", type=int, default=cores, help="num cpu cores to use for tag scanning")
+    ap2.add_argument("--mtag-mt", metavar="CORES", type=int, default=CORES, help="num cpu cores to use for tag scanning")
     ap2.add_argument("--mtag-v", action="store_true", help="verbose tag scanning; print errors from mtp subprocesses and such")
     ap2.add_argument("-mtm", metavar="M=t,t,t", type=u, action="append", help="add/replace metadata mapping")
     ap2.add_argument("-mte", metavar="M,M,M", type=u, help="tags to index/display (comma-sep.)",

copyparty/broker_mp.py

@@ -6,7 +6,7 @@ import time
 
 import queue
 
-from .__init__ import TYPE_CHECKING
+from .__init__ import TYPE_CHECKING, CORES
 from .broker_mpw import MpWorker
 from .broker_util import try_exec
 from .util import mp
@@ -44,7 +44,7 @@ class BrokerMp(object):
         self.procs = []
         self.mutex = threading.Lock()
 
-        self.num_workers = self.args.j or mp.cpu_count()
+        self.num_workers = self.args.j or CORES
         self.log("broker", "booting {} subprocesses".format(self.num_workers))
         for n in range(1, self.num_workers + 1):
             q_pend: queue.Queue[tuple[int, str, list[Any]]] = mp.Queue(1)

copyparty/svchub.py

@@ -501,7 +501,10 @@ class SvcHub(object):
         if self.args.j == 1:
             return False
 
-        if mp.cpu_count() <= 1:
+        try:
+            if mp.cpu_count() <= 1:
+                raise Exception()
+        except:
             self.log("svchub", "only one CPU detected; multiprocessing disabled")
             return False