Upload backend/venv/lib/python3.10/site-packages/diskcache/recipes.py with huggingface_hub
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backend/venv/lib/python3.10/site-packages/diskcache/recipes.py
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| 1 |
+
"""Disk Cache Recipes
|
| 2 |
+
"""
|
| 3 |
+
|
| 4 |
+
import functools
|
| 5 |
+
import math
|
| 6 |
+
import os
|
| 7 |
+
import random
|
| 8 |
+
import threading
|
| 9 |
+
import time
|
| 10 |
+
|
| 11 |
+
from .core import ENOVAL, args_to_key, full_name
|
| 12 |
+
|
| 13 |
+
|
| 14 |
+
class Averager:
|
| 15 |
+
"""Recipe for calculating a running average.
|
| 16 |
+
|
| 17 |
+
Sometimes known as "online statistics," the running average maintains the
|
| 18 |
+
total and count. The average can then be calculated at any time.
|
| 19 |
+
|
| 20 |
+
Assumes the key will not be evicted. Set the eviction policy to 'none' on
|
| 21 |
+
the cache to guarantee the key is not evicted.
|
| 22 |
+
|
| 23 |
+
>>> import diskcache
|
| 24 |
+
>>> cache = diskcache.FanoutCache()
|
| 25 |
+
>>> ave = Averager(cache, 'latency')
|
| 26 |
+
>>> ave.add(0.080)
|
| 27 |
+
>>> ave.add(0.120)
|
| 28 |
+
>>> ave.get()
|
| 29 |
+
0.1
|
| 30 |
+
>>> ave.add(0.160)
|
| 31 |
+
>>> ave.pop()
|
| 32 |
+
0.12
|
| 33 |
+
>>> print(ave.get())
|
| 34 |
+
None
|
| 35 |
+
|
| 36 |
+
"""
|
| 37 |
+
|
| 38 |
+
def __init__(self, cache, key, expire=None, tag=None):
|
| 39 |
+
self._cache = cache
|
| 40 |
+
self._key = key
|
| 41 |
+
self._expire = expire
|
| 42 |
+
self._tag = tag
|
| 43 |
+
|
| 44 |
+
def add(self, value):
|
| 45 |
+
"""Add `value` to average."""
|
| 46 |
+
with self._cache.transact(retry=True):
|
| 47 |
+
total, count = self._cache.get(self._key, default=(0.0, 0))
|
| 48 |
+
total += value
|
| 49 |
+
count += 1
|
| 50 |
+
self._cache.set(
|
| 51 |
+
self._key,
|
| 52 |
+
(total, count),
|
| 53 |
+
expire=self._expire,
|
| 54 |
+
tag=self._tag,
|
| 55 |
+
)
|
| 56 |
+
|
| 57 |
+
def get(self):
|
| 58 |
+
"""Get current average or return `None` if count equals zero."""
|
| 59 |
+
total, count = self._cache.get(self._key, default=(0.0, 0), retry=True)
|
| 60 |
+
return None if count == 0 else total / count
|
| 61 |
+
|
| 62 |
+
def pop(self):
|
| 63 |
+
"""Return current average and delete key."""
|
| 64 |
+
total, count = self._cache.pop(self._key, default=(0.0, 0), retry=True)
|
| 65 |
+
return None if count == 0 else total / count
|
| 66 |
+
|
| 67 |
+
|
| 68 |
+
class Lock:
|
| 69 |
+
"""Recipe for cross-process and cross-thread lock.
|
| 70 |
+
|
| 71 |
+
Assumes the key will not be evicted. Set the eviction policy to 'none' on
|
| 72 |
+
the cache to guarantee the key is not evicted.
|
| 73 |
+
|
| 74 |
+
>>> import diskcache
|
| 75 |
+
>>> cache = diskcache.Cache()
|
| 76 |
+
>>> lock = Lock(cache, 'report-123')
|
| 77 |
+
>>> lock.acquire()
|
| 78 |
+
>>> lock.release()
|
| 79 |
+
>>> with lock:
|
| 80 |
+
... pass
|
| 81 |
+
|
| 82 |
+
"""
|
| 83 |
+
|
| 84 |
+
def __init__(self, cache, key, expire=None, tag=None):
|
| 85 |
+
self._cache = cache
|
| 86 |
+
self._key = key
|
| 87 |
+
self._expire = expire
|
| 88 |
+
self._tag = tag
|
| 89 |
+
|
| 90 |
+
def acquire(self):
|
| 91 |
+
"""Acquire lock using spin-lock algorithm."""
|
| 92 |
+
while True:
|
| 93 |
+
added = self._cache.add(
|
| 94 |
+
self._key,
|
| 95 |
+
None,
|
| 96 |
+
expire=self._expire,
|
| 97 |
+
tag=self._tag,
|
| 98 |
+
retry=True,
|
| 99 |
+
)
|
| 100 |
+
if added:
|
| 101 |
+
break
|
| 102 |
+
time.sleep(0.001)
|
| 103 |
+
|
| 104 |
+
def release(self):
|
| 105 |
+
"""Release lock by deleting key."""
|
| 106 |
+
self._cache.delete(self._key, retry=True)
|
| 107 |
+
|
| 108 |
+
def locked(self):
|
| 109 |
+
"""Return true if the lock is acquired."""
|
| 110 |
+
return self._key in self._cache
|
| 111 |
+
|
| 112 |
+
def __enter__(self):
|
| 113 |
+
self.acquire()
|
| 114 |
+
|
| 115 |
+
def __exit__(self, *exc_info):
|
| 116 |
+
self.release()
|
| 117 |
+
|
| 118 |
+
|
| 119 |
+
class RLock:
|
| 120 |
+
"""Recipe for cross-process and cross-thread re-entrant lock.
|
| 121 |
+
|
| 122 |
+
Assumes the key will not be evicted. Set the eviction policy to 'none' on
|
| 123 |
+
the cache to guarantee the key is not evicted.
|
| 124 |
+
|
| 125 |
+
>>> import diskcache
|
| 126 |
+
>>> cache = diskcache.Cache()
|
| 127 |
+
>>> rlock = RLock(cache, 'user-123')
|
| 128 |
+
>>> rlock.acquire()
|
| 129 |
+
>>> rlock.acquire()
|
| 130 |
+
>>> rlock.release()
|
| 131 |
+
>>> with rlock:
|
| 132 |
+
... pass
|
| 133 |
+
>>> rlock.release()
|
| 134 |
+
>>> rlock.release()
|
| 135 |
+
Traceback (most recent call last):
|
| 136 |
+
...
|
| 137 |
+
AssertionError: cannot release un-acquired lock
|
| 138 |
+
|
| 139 |
+
"""
|
| 140 |
+
|
| 141 |
+
def __init__(self, cache, key, expire=None, tag=None):
|
| 142 |
+
self._cache = cache
|
| 143 |
+
self._key = key
|
| 144 |
+
self._expire = expire
|
| 145 |
+
self._tag = tag
|
| 146 |
+
|
| 147 |
+
def acquire(self):
|
| 148 |
+
"""Acquire lock by incrementing count using spin-lock algorithm."""
|
| 149 |
+
pid = os.getpid()
|
| 150 |
+
tid = threading.get_ident()
|
| 151 |
+
pid_tid = '{}-{}'.format(pid, tid)
|
| 152 |
+
|
| 153 |
+
while True:
|
| 154 |
+
with self._cache.transact(retry=True):
|
| 155 |
+
value, count = self._cache.get(self._key, default=(None, 0))
|
| 156 |
+
if pid_tid == value or count == 0:
|
| 157 |
+
self._cache.set(
|
| 158 |
+
self._key,
|
| 159 |
+
(pid_tid, count + 1),
|
| 160 |
+
expire=self._expire,
|
| 161 |
+
tag=self._tag,
|
| 162 |
+
)
|
| 163 |
+
return
|
| 164 |
+
time.sleep(0.001)
|
| 165 |
+
|
| 166 |
+
def release(self):
|
| 167 |
+
"""Release lock by decrementing count."""
|
| 168 |
+
pid = os.getpid()
|
| 169 |
+
tid = threading.get_ident()
|
| 170 |
+
pid_tid = '{}-{}'.format(pid, tid)
|
| 171 |
+
|
| 172 |
+
with self._cache.transact(retry=True):
|
| 173 |
+
value, count = self._cache.get(self._key, default=(None, 0))
|
| 174 |
+
is_owned = pid_tid == value and count > 0
|
| 175 |
+
assert is_owned, 'cannot release un-acquired lock'
|
| 176 |
+
self._cache.set(
|
| 177 |
+
self._key,
|
| 178 |
+
(value, count - 1),
|
| 179 |
+
expire=self._expire,
|
| 180 |
+
tag=self._tag,
|
| 181 |
+
)
|
| 182 |
+
|
| 183 |
+
def __enter__(self):
|
| 184 |
+
self.acquire()
|
| 185 |
+
|
| 186 |
+
def __exit__(self, *exc_info):
|
| 187 |
+
self.release()
|
| 188 |
+
|
| 189 |
+
|
| 190 |
+
class BoundedSemaphore:
|
| 191 |
+
"""Recipe for cross-process and cross-thread bounded semaphore.
|
| 192 |
+
|
| 193 |
+
Assumes the key will not be evicted. Set the eviction policy to 'none' on
|
| 194 |
+
the cache to guarantee the key is not evicted.
|
| 195 |
+
|
| 196 |
+
>>> import diskcache
|
| 197 |
+
>>> cache = diskcache.Cache()
|
| 198 |
+
>>> semaphore = BoundedSemaphore(cache, 'max-cons', value=2)
|
| 199 |
+
>>> semaphore.acquire()
|
| 200 |
+
>>> semaphore.acquire()
|
| 201 |
+
>>> semaphore.release()
|
| 202 |
+
>>> with semaphore:
|
| 203 |
+
... pass
|
| 204 |
+
>>> semaphore.release()
|
| 205 |
+
>>> semaphore.release()
|
| 206 |
+
Traceback (most recent call last):
|
| 207 |
+
...
|
| 208 |
+
AssertionError: cannot release un-acquired semaphore
|
| 209 |
+
|
| 210 |
+
"""
|
| 211 |
+
|
| 212 |
+
def __init__(self, cache, key, value=1, expire=None, tag=None):
|
| 213 |
+
self._cache = cache
|
| 214 |
+
self._key = key
|
| 215 |
+
self._value = value
|
| 216 |
+
self._expire = expire
|
| 217 |
+
self._tag = tag
|
| 218 |
+
|
| 219 |
+
def acquire(self):
|
| 220 |
+
"""Acquire semaphore by decrementing value using spin-lock algorithm."""
|
| 221 |
+
while True:
|
| 222 |
+
with self._cache.transact(retry=True):
|
| 223 |
+
value = self._cache.get(self._key, default=self._value)
|
| 224 |
+
if value > 0:
|
| 225 |
+
self._cache.set(
|
| 226 |
+
self._key,
|
| 227 |
+
value - 1,
|
| 228 |
+
expire=self._expire,
|
| 229 |
+
tag=self._tag,
|
| 230 |
+
)
|
| 231 |
+
return
|
| 232 |
+
time.sleep(0.001)
|
| 233 |
+
|
| 234 |
+
def release(self):
|
| 235 |
+
"""Release semaphore by incrementing value."""
|
| 236 |
+
with self._cache.transact(retry=True):
|
| 237 |
+
value = self._cache.get(self._key, default=self._value)
|
| 238 |
+
assert self._value > value, 'cannot release un-acquired semaphore'
|
| 239 |
+
value += 1
|
| 240 |
+
self._cache.set(
|
| 241 |
+
self._key,
|
| 242 |
+
value,
|
| 243 |
+
expire=self._expire,
|
| 244 |
+
tag=self._tag,
|
| 245 |
+
)
|
| 246 |
+
|
| 247 |
+
def __enter__(self):
|
| 248 |
+
self.acquire()
|
| 249 |
+
|
| 250 |
+
def __exit__(self, *exc_info):
|
| 251 |
+
self.release()
|
| 252 |
+
|
| 253 |
+
|
| 254 |
+
def throttle(
|
| 255 |
+
cache,
|
| 256 |
+
count,
|
| 257 |
+
seconds,
|
| 258 |
+
name=None,
|
| 259 |
+
expire=None,
|
| 260 |
+
tag=None,
|
| 261 |
+
time_func=time.time,
|
| 262 |
+
sleep_func=time.sleep,
|
| 263 |
+
):
|
| 264 |
+
"""Decorator to throttle calls to function.
|
| 265 |
+
|
| 266 |
+
Assumes keys will not be evicted. Set the eviction policy to 'none' on the
|
| 267 |
+
cache to guarantee the keys are not evicted.
|
| 268 |
+
|
| 269 |
+
>>> import diskcache, time
|
| 270 |
+
>>> cache = diskcache.Cache()
|
| 271 |
+
>>> count = 0
|
| 272 |
+
>>> @throttle(cache, 2, 1) # 2 calls per 1 second
|
| 273 |
+
... def increment():
|
| 274 |
+
... global count
|
| 275 |
+
... count += 1
|
| 276 |
+
>>> start = time.time()
|
| 277 |
+
>>> while (time.time() - start) <= 2:
|
| 278 |
+
... increment()
|
| 279 |
+
>>> count in (6, 7) # 6 or 7 calls depending on CPU load
|
| 280 |
+
True
|
| 281 |
+
|
| 282 |
+
"""
|
| 283 |
+
|
| 284 |
+
def decorator(func):
|
| 285 |
+
rate = count / float(seconds)
|
| 286 |
+
key = full_name(func) if name is None else name
|
| 287 |
+
now = time_func()
|
| 288 |
+
cache.set(key, (now, count), expire=expire, tag=tag, retry=True)
|
| 289 |
+
|
| 290 |
+
@functools.wraps(func)
|
| 291 |
+
def wrapper(*args, **kwargs):
|
| 292 |
+
while True:
|
| 293 |
+
with cache.transact(retry=True):
|
| 294 |
+
last, tally = cache.get(key)
|
| 295 |
+
now = time_func()
|
| 296 |
+
tally += (now - last) * rate
|
| 297 |
+
delay = 0
|
| 298 |
+
|
| 299 |
+
if tally > count:
|
| 300 |
+
cache.set(key, (now, count - 1), expire)
|
| 301 |
+
elif tally >= 1:
|
| 302 |
+
cache.set(key, (now, tally - 1), expire)
|
| 303 |
+
else:
|
| 304 |
+
delay = (1 - tally) / rate
|
| 305 |
+
|
| 306 |
+
if delay:
|
| 307 |
+
sleep_func(delay)
|
| 308 |
+
else:
|
| 309 |
+
break
|
| 310 |
+
|
| 311 |
+
return func(*args, **kwargs)
|
| 312 |
+
|
| 313 |
+
return wrapper
|
| 314 |
+
|
| 315 |
+
return decorator
|
| 316 |
+
|
| 317 |
+
|
| 318 |
+
def barrier(cache, lock_factory, name=None, expire=None, tag=None):
|
| 319 |
+
"""Barrier to calling decorated function.
|
| 320 |
+
|
| 321 |
+
Supports different kinds of locks: Lock, RLock, BoundedSemaphore.
|
| 322 |
+
|
| 323 |
+
Assumes keys will not be evicted. Set the eviction policy to 'none' on the
|
| 324 |
+
cache to guarantee the keys are not evicted.
|
| 325 |
+
|
| 326 |
+
>>> import diskcache, time
|
| 327 |
+
>>> cache = diskcache.Cache()
|
| 328 |
+
>>> @barrier(cache, Lock)
|
| 329 |
+
... def work(num):
|
| 330 |
+
... print('worker started')
|
| 331 |
+
... time.sleep(1)
|
| 332 |
+
... print('worker finished')
|
| 333 |
+
>>> import multiprocessing.pool
|
| 334 |
+
>>> pool = multiprocessing.pool.ThreadPool(2)
|
| 335 |
+
>>> _ = pool.map(work, range(2))
|
| 336 |
+
worker started
|
| 337 |
+
worker finished
|
| 338 |
+
worker started
|
| 339 |
+
worker finished
|
| 340 |
+
>>> pool.terminate()
|
| 341 |
+
|
| 342 |
+
"""
|
| 343 |
+
|
| 344 |
+
def decorator(func):
|
| 345 |
+
key = full_name(func) if name is None else name
|
| 346 |
+
lock = lock_factory(cache, key, expire=expire, tag=tag)
|
| 347 |
+
|
| 348 |
+
@functools.wraps(func)
|
| 349 |
+
def wrapper(*args, **kwargs):
|
| 350 |
+
with lock:
|
| 351 |
+
return func(*args, **kwargs)
|
| 352 |
+
|
| 353 |
+
return wrapper
|
| 354 |
+
|
| 355 |
+
return decorator
|
| 356 |
+
|
| 357 |
+
|
| 358 |
+
def memoize_stampede(
|
| 359 |
+
cache, expire, name=None, typed=False, tag=None, beta=1, ignore=()
|
| 360 |
+
):
|
| 361 |
+
"""Memoizing cache decorator with cache stampede protection.
|
| 362 |
+
|
| 363 |
+
Cache stampedes are a type of system overload that can occur when parallel
|
| 364 |
+
computing systems using memoization come under heavy load. This behaviour
|
| 365 |
+
is sometimes also called dog-piling, cache miss storm, cache choking, or
|
| 366 |
+
the thundering herd problem.
|
| 367 |
+
|
| 368 |
+
The memoization decorator implements cache stampede protection through
|
| 369 |
+
early recomputation. Early recomputation of function results will occur
|
| 370 |
+
probabilistically before expiration in a background thread of
|
| 371 |
+
execution. Early probabilistic recomputation is based on research by
|
| 372 |
+
Vattani, A.; Chierichetti, F.; Lowenstein, K. (2015), Optimal Probabilistic
|
| 373 |
+
Cache Stampede Prevention, VLDB, pp. 886-897, ISSN 2150-8097
|
| 374 |
+
|
| 375 |
+
If name is set to None (default), the callable name will be determined
|
| 376 |
+
automatically.
|
| 377 |
+
|
| 378 |
+
If typed is set to True, function arguments of different types will be
|
| 379 |
+
cached separately. For example, f(3) and f(3.0) will be treated as distinct
|
| 380 |
+
calls with distinct results.
|
| 381 |
+
|
| 382 |
+
The original underlying function is accessible through the `__wrapped__`
|
| 383 |
+
attribute. This is useful for introspection, for bypassing the cache, or
|
| 384 |
+
for rewrapping the function with a different cache.
|
| 385 |
+
|
| 386 |
+
>>> from diskcache import Cache
|
| 387 |
+
>>> cache = Cache()
|
| 388 |
+
>>> @memoize_stampede(cache, expire=1)
|
| 389 |
+
... def fib(number):
|
| 390 |
+
... if number == 0:
|
| 391 |
+
... return 0
|
| 392 |
+
... elif number == 1:
|
| 393 |
+
... return 1
|
| 394 |
+
... else:
|
| 395 |
+
... return fib(number - 1) + fib(number - 2)
|
| 396 |
+
>>> print(fib(100))
|
| 397 |
+
354224848179261915075
|
| 398 |
+
|
| 399 |
+
An additional `__cache_key__` attribute can be used to generate the cache
|
| 400 |
+
key used for the given arguments.
|
| 401 |
+
|
| 402 |
+
>>> key = fib.__cache_key__(100)
|
| 403 |
+
>>> del cache[key]
|
| 404 |
+
|
| 405 |
+
Remember to call memoize when decorating a callable. If you forget, then a
|
| 406 |
+
TypeError will occur.
|
| 407 |
+
|
| 408 |
+
:param cache: cache to store callable arguments and return values
|
| 409 |
+
:param float expire: seconds until arguments expire
|
| 410 |
+
:param str name: name given for callable (default None, automatic)
|
| 411 |
+
:param bool typed: cache different types separately (default False)
|
| 412 |
+
:param str tag: text to associate with arguments (default None)
|
| 413 |
+
:param set ignore: positional or keyword args to ignore (default ())
|
| 414 |
+
:return: callable decorator
|
| 415 |
+
|
| 416 |
+
"""
|
| 417 |
+
# Caution: Nearly identical code exists in Cache.memoize
|
| 418 |
+
def decorator(func):
|
| 419 |
+
"""Decorator created by memoize call for callable."""
|
| 420 |
+
base = (full_name(func),) if name is None else (name,)
|
| 421 |
+
|
| 422 |
+
def timer(*args, **kwargs):
|
| 423 |
+
"""Time execution of `func` and return result and time delta."""
|
| 424 |
+
start = time.time()
|
| 425 |
+
result = func(*args, **kwargs)
|
| 426 |
+
delta = time.time() - start
|
| 427 |
+
return result, delta
|
| 428 |
+
|
| 429 |
+
@functools.wraps(func)
|
| 430 |
+
def wrapper(*args, **kwargs):
|
| 431 |
+
"""Wrapper for callable to cache arguments and return values."""
|
| 432 |
+
key = wrapper.__cache_key__(*args, **kwargs)
|
| 433 |
+
pair, expire_time = cache.get(
|
| 434 |
+
key,
|
| 435 |
+
default=ENOVAL,
|
| 436 |
+
expire_time=True,
|
| 437 |
+
retry=True,
|
| 438 |
+
)
|
| 439 |
+
|
| 440 |
+
if pair is not ENOVAL:
|
| 441 |
+
result, delta = pair
|
| 442 |
+
now = time.time()
|
| 443 |
+
ttl = expire_time - now
|
| 444 |
+
|
| 445 |
+
if (-delta * beta * math.log(random.random())) < ttl:
|
| 446 |
+
return result # Cache hit.
|
| 447 |
+
|
| 448 |
+
# Check whether a thread has started for early recomputation.
|
| 449 |
+
|
| 450 |
+
thread_key = key + (ENOVAL,)
|
| 451 |
+
thread_added = cache.add(
|
| 452 |
+
thread_key,
|
| 453 |
+
None,
|
| 454 |
+
expire=delta,
|
| 455 |
+
retry=True,
|
| 456 |
+
)
|
| 457 |
+
|
| 458 |
+
if thread_added:
|
| 459 |
+
# Start thread for early recomputation.
|
| 460 |
+
def recompute():
|
| 461 |
+
with cache:
|
| 462 |
+
pair = timer(*args, **kwargs)
|
| 463 |
+
cache.set(
|
| 464 |
+
key,
|
| 465 |
+
pair,
|
| 466 |
+
expire=expire,
|
| 467 |
+
tag=tag,
|
| 468 |
+
retry=True,
|
| 469 |
+
)
|
| 470 |
+
|
| 471 |
+
thread = threading.Thread(target=recompute)
|
| 472 |
+
thread.daemon = True
|
| 473 |
+
thread.start()
|
| 474 |
+
|
| 475 |
+
return result
|
| 476 |
+
|
| 477 |
+
pair = timer(*args, **kwargs)
|
| 478 |
+
cache.set(key, pair, expire=expire, tag=tag, retry=True)
|
| 479 |
+
return pair[0]
|
| 480 |
+
|
| 481 |
+
def __cache_key__(*args, **kwargs):
|
| 482 |
+
"""Make key for cache given function arguments."""
|
| 483 |
+
return args_to_key(base, args, kwargs, typed, ignore)
|
| 484 |
+
|
| 485 |
+
wrapper.__cache_key__ = __cache_key__
|
| 486 |
+
return wrapper
|
| 487 |
+
|
| 488 |
+
return decorator
|