bitbake: bitbake-worker/cooker: Increase default pipe size

The default pipe size is 64kb on builds, which can be inefficient
for larger log files from workers. Increase the pipe size to 512kb
since build systems have decent amounts of memory and this is a more
efficient way of batching the data.

Tweak the default read sizes to match the pipe size for efficiency.

Since the contstant is only present in python 3.10 onwards, add
some compatibility code.

(Bitbake rev: 69c14e46600ba5ae9703f67704ab2548875ae6d7)

Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>

bitbake/bin/bitbake-worker

@@ -21,9 +21,14 @@ import traceback
 import queue
 import shlex
 import subprocess
+import fcntl
 from multiprocessing import Lock
 from threading import Thread
 
+# Remove when we have a minimum of python 3.10
+if not hasattr(fcntl, 'F_SETPIPE_SZ'):
+    fcntl.F_SETPIPE_SZ = 1031
+
 bb.utils.check_system_locale()
 
 # Users shouldn't be running this code directly
@@ -44,7 +49,6 @@ if sys.argv[1].startswith("decafbadbad"):
 # updates to log files for use with tail
 try:
     if sys.stdout.name == '<stdout>':
-        import fcntl
         fl = fcntl.fcntl(sys.stdout.fileno(), fcntl.F_GETFL)
         fl |= os.O_SYNC 
         fcntl.fcntl(sys.stdout.fileno(), fcntl.F_SETFL, fl)
@@ -56,6 +60,12 @@ logger = logging.getLogger("BitBake")
 
 worker_pipe = sys.stdout.fileno()
 bb.utils.nonblockingfd(worker_pipe)
+# Try to make the pipe buffers larger as it is much more efficient. If we can't
+# e.g. out of buffer space (/proc/sys/fs/pipe-user-pages-soft) then just pass over.
+try:
+    fcntl.fcntl(worker_pipe, fcntl.F_SETPIPE_SZ, 512 * 1024)
+except:
+    pass
 # Need to guard against multiprocessing being used in child processes
 # and multiple processes trying to write to the parent at the same time
 worker_pipe_lock = None
@@ -357,7 +367,7 @@ class runQueueWorkerPipe():
     def read(self):
         start = len(self.queue)
         try:
-            self.queue.extend(self.input.read(102400) or b"")
+            self.queue.extend(self.input.read(512*1024) or b"")
         except (OSError, IOError) as e:
             if e.errno != errno.EAGAIN:
                 raise

bitbake/lib/bb/runqueue.py

@@ -3318,7 +3318,7 @@ class runQueuePipe():
 
         start = len(self.queue)
         try:
-            self.queue.extend(self.input.read(102400) or b"")
+            self.queue.extend(self.input.read(512 * 1024) or b"")
         except (OSError, IOError) as e:
             if e.errno != errno.EAGAIN:
                 raise