remove constant _MAXIMUM_BUFFER_SIZE

python · gpshead · Mar 7, 2025 · Feb 5, 2025 · Feb 5, 2025 · Feb 5, 2025
commit 7ce54c4c7627e579c2e1c52b9918eeff3375e6c0
diff --git a/Doc/library/functions.rst b/Doc/library/functions.rst
@@ -1406,7 +1406,7 @@ are always available.  They are listed here in alphabetical order.
    given, the default buffering policy works as follows:
 
    * Binary files are buffered in fixed-size chunks; the size of the buffer
-     is max(min(blocksize, _MAXIMUM_BUFFER_SIZE), DEFAULT_BUFFER_SIZE)
+     is max(min(blocksize, 8 MiB), DEFAULT_BUFFER_SIZE)
      when the device block size is available.
      On most systems, the buffer will typically be 128 kilobytes long.
 

diff --git a/Lib/_pyio.py b/Lib/_pyio.py
@@ -23,10 +23,9 @@
     valid_seek_flags.add(os.SEEK_HOLE)
     valid_seek_flags.add(os.SEEK_DATA)
 
-# open() uses max(min(blocksize, _MAXIMUM_BUFFER_SIZE), DEFAULT_BUFFER_SIZE)
+# open() uses max(min(blocksize, 8 MiB), DEFAULT_BUFFER_SIZE)
 # when the device block size is available.
 DEFAULT_BUFFER_SIZE = 128 * 1024  # bytes
-_MAXIMUM_BUFFER_SIZE = 8192 * 1024  # bytes
 
 # NOTE: Base classes defined here are registered with the "official" ABCs
 # defined in io.py. We don't use real inheritance though, because we don't want
@@ -126,7 +125,7 @@ def open(file, mode="r", buffering=-1, encoding=None, errors=None,
     given, the default buffering policy works as follows:
 
    * Binary files are buffered in fixed-size chunks; the size of the buffer
-     is max(min(blocksize, _MAXIMUM_BUFFER_SIZE), DEFAULT_BUFFER_SIZE)
+     is max(min(blocksize, 8 MiB), DEFAULT_BUFFER_SIZE)
      when the device block size is available.
      On most systems, the buffer will typically be 128 kilobytes long.
 
@@ -244,7 +243,7 @@ def open(file, mode="r", buffering=-1, encoding=None, errors=None,
             buffering = -1
             line_buffering = True
         if buffering < 0:
-            buffering = max(min(raw._blksize, _MAXIMUM_BUFFER_SIZE), DEFAULT_BUFFER_SIZE)
+            buffering = max(min(raw._blksize, 8192 * 1024), DEFAULT_BUFFER_SIZE)
         if buffering < 0:
             raise ValueError("invalid buffering size")
         if buffering == 0:

diff --git a/Modules/_io/_iomodule.c b/Modules/_io/_iomodule.c
@@ -60,11 +60,6 @@ PyDoc_STRVAR(module_doc,
 "DEFAULT_BUFFER_SIZE\n"
 "\n"
 "   An int containing the default buffer size used by the module's buffered\n"
-"   I/O classes.\n"
-"\n"
-"_MAXIMUM_BUFFER_SIZE\n"
-"\n"
-"   An int containing the maximum buffer size used by the module's buffered\n"
 "   I/O classes.\n"
     );
 
@@ -136,7 +131,7 @@ the size of a fixed-size chunk buffer.  When no buffering argument is
 given, the default buffering policy works as follows:
 
 * Binary files are buffered in fixed-size chunks; the size of the buffer
- is max(min(blocksize, _MAXIMUM_BUFFER_SIZE), DEFAULT_BUFFER_SIZE)
+ is max(min(blocksize, 8 MiB), DEFAULT_BUFFER_SIZE)
  when the device block size is available.
  On most systems, the buffer will typically be 128 kilobytes long.
 
@@ -204,7 +199,7 @@ static PyObject *
 _io_open_impl(PyObject *module, PyObject *file, const char *mode,
               int buffering, const char *encoding, const char *errors,
               const char *newline, int closefd, PyObject *opener)
-/*[clinic end generated code: output=aefafc4ce2b46dc0 input=a35153cf2829c537]*/
+/*[clinic end generated code: output=aefafc4ce2b46dc0 input=28027fdaabb8d744]*/
 {
     size_t i;
 
@@ -372,7 +367,7 @@ _io_open_impl(PyObject *module, PyObject *file, const char *mode,
         if (blksize_obj == NULL)
             goto error;
         buffering = PyLong_AsLong(blksize_obj);
-        buffering = Py_MAX(Py_MIN(buffering, _MAXIMUM_BUFFER_SIZE), DEFAULT_BUFFER_SIZE);
+        buffering = Py_MAX(Py_MIN(buffering, 8192 * 1024), DEFAULT_BUFFER_SIZE);
         Py_DECREF(blksize_obj);
         if (buffering == -1 && PyErr_Occurred())
             goto error;

diff --git a/Modules/_io/_iomodule.h b/Modules/_io/_iomodule.h
@@ -79,7 +79,6 @@ extern Py_ssize_t _PyIO_find_line_ending(
 extern int _PyIO_trap_eintr(void);
 
 #define DEFAULT_BUFFER_SIZE (128 * 1024)  /* bytes */
-#define _MAXIMUM_BUFFER_SIZE (8192 * 1024)  /* bytes */
 
 /*
  * Offset type for positioning.

diff --git a/Modules/_io/clinic/_iomodule.c.h b/Modules/_io/clinic/_iomodule.c.h