import gc
from pathlib import Path
from sys import getsizeof
import time
from typing import Tuple
import lz4.frame as gzip
from py3dtiles.points.utils import node_name_to_path
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class SharedNodeStore:
def __init__(self, folder: Path) -> None:
self.metadata = {}
self.data = []
self.folder = folder
self.stats = {
'hit': 0,
'miss': 0,
'new': 0,
}
self.memory_size = {
'content': 0,
'container': getsizeof(self.data) + getsizeof(self.metadata),
}
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def control_memory_usage(self, max_size_mb: int, verbose: int) -> None:
bytes_to_mb = 1.0 / (1024 * 1024)
max_size_mb = max(max_size_mb, 200)
if verbose >= 3:
self.print_statistics()
# guess cache size
cache_size = (self.memory_size['container'] + self.memory_size['content']) * bytes_to_mb
before = cache_size
if before < max_size_mb:
return
if verbose >= 2:
print('>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> CACHE CLEANING [{}]'.format(before))
self.remove_oldest_nodes(1 - max_size_mb / before)
gc.collect()
if verbose >= 2:
print('<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<< CACHE CLEANING')
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def get(self, name: bytes, stat_inc: int = 1) -> bytes:
metadata = self.metadata.get(name, None)
data = b''
if metadata is not None:
data = self.data[metadata[1]]
self.stats['hit'] += stat_inc
else:
node_path = node_name_to_path(self.folder, name)
if node_path.exists():
self.stats['miss'] += stat_inc
with node_path.open('rb') as f:
data = f.read()
else:
self.stats['new'] += stat_inc
# should we cache this node?
return data
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def remove(self, name: bytes) -> None:
meta = self.metadata.pop(name, None)
node_path = node_name_to_path(self.folder, name)
if meta is None and not node_path.exists():
raise FileNotFoundError(f"{node_path} should exist")
else:
self.memory_size['content'] -= getsizeof(meta)
self.memory_size['content'] -= len(self.data[meta[1]])
self.memory_size['container'] = getsizeof(self.data) + getsizeof(self.metadata)
self.data[meta[1]] = None
if node_path.exists():
node_path.unlink()
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def put(self, name: bytes, data: bytes) -> None:
compressed_data = gzip.compress(data)
metadata = self.metadata.get(name, None)
if metadata is None:
metadata = (time.time(), len(self.data))
self.data.append(compressed_data)
else:
metadata = (time.time(), metadata[1])
self.data[metadata[1]] = compressed_data
self.metadata.update([(name, metadata)])
self.memory_size['content'] += len(compressed_data) + getsizeof((name, metadata))
self.memory_size['container'] = getsizeof(self.data) + getsizeof(self.metadata)
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def remove_oldest_nodes(self, percent) -> Tuple[int, int]:
count = _remove_all(self)
self.memory_size['content'] = 0
self.memory_size['container'] = getsizeof(self.data) + getsizeof(self.metadata)
assert len(self.metadata) == 0
assert len(self.data) == 0
return count
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def print_statistics(self) -> None:
print('Stats: Hits = {}, Miss = {}, New = {}'.format(
self.stats['hit'],
self.stats['miss'],
self.stats['new']))
def _remove_all(store: SharedNodeStore) -> Tuple[int, int]:
# delete the entries
count = len(store.metadata)
bytes_written = 0
for name, meta in store.metadata.items():
data = store.data[meta[1]]
node_path = node_name_to_path(store.folder, name)
with node_path.open('wb') as f:
bytes_written += f.write(data)
store.metadata = {}
store.data = []
return count, bytes_written