| @@ -60,26 +60,32 @@ def __setstate__(self, state): |
|
|
| 60 |
60 |
else: |
| 61 |
61 |
|
| 62 |
62 |
class Arena(object): |
|
63 |
+if sys.platform == 'linux': |
|
64 |
+_dir_candidates = ['/dev/shm'] |
|
65 |
+else: |
|
66 |
+_dir_candidates = [] |
| 63 |
67 |
|
| 64 |
68 |
def __init__(self, size, fd=-1): |
| 65 |
69 |
self.size = size |
| 66 |
70 |
self.fd = fd |
| 67 |
71 |
if fd == -1: |
| 68 |
72 |
self.fd, name = tempfile.mkstemp( |
| 69 |
|
-prefix='pym-%d-'%os.getpid(), dir=util.get_temp_dir()) |
|
73 |
+prefix='pym-%d-'%os.getpid(), |
|
74 |
+dir=self._choose_dir(size)) |
| 70 |
75 |
os.unlink(name) |
| 71 |
76 |
util.Finalize(self, os.close, (self.fd,)) |
| 72 |
|
-with open(self.fd, 'wb', closefd=False) as f: |
| 73 |
|
-bs = 1024 * 1024 |
| 74 |
|
-if size >= bs: |
| 75 |
|
-zeros = b'\0' * bs |
| 76 |
|
-for _ in range(size // bs): |
| 77 |
|
-f.write(zeros) |
| 78 |
|
-del zeros |
| 79 |
|
-f.write(b'\0' * (size % bs)) |
| 80 |
|
-assert f.tell() == size |
|
77 |
+os.ftruncate(self.fd, size) |
| 81 |
78 |
self.buffer = mmap.mmap(self.fd, self.size) |
| 82 |
79 |
|
|
80 |
+def _choose_dir(self, size): |
|
81 |
+# Choose a non-storage backed directory if possible, |
|
82 |
+# to improve performance |
|
83 |
+for d in self._dir_candidates: |
|
84 |
+st = os.statvfs(d) |
|
85 |
+if st.f_bavail * st.f_frsize >= size: # enough free space? |
|
86 |
+return d |
|
87 |
+return util.get_temp_dir() |
|
88 |
+ |
| 83 |
89 |
def reduce_arena(a): |
| 84 |
90 |
if a.fd == -1: |
| 85 |
91 |
raise ValueError('Arena is unpicklable because ' |