- 在CacheManager中添加健康监控系统,并提供详细的内存统计信息 - 使用新的memory_utils模块实现精确的内存估算 - 添加基于大小的缓存条目限制,以防止过大项目 - 通过去重内存计算优化缓存统计 - 在MultiLevelCache中添加过期条目的自动清理功能 - 增强批处理调度器缓存功能,支持LRU驱逐策略和内存追踪 - 更新配置以支持最大项目大小限制 - 添加全面的内存分析文档和工具 重大变更:CacheManager 的默认 TTL 参数现改为 None 而非 3600。数据库兼容层默认禁用缓存,以防止旧版代码过度使用缓存。
644 lines
22 KiB
Python
644 lines
22 KiB
Python
"""多级缓存管理器
|
||
|
||
实现高性能的多级缓存系统:
|
||
- L1缓存:内存缓存,1000项,60秒TTL,用于热点数据
|
||
- L2缓存:扩展缓存,10000项,300秒TTL,用于温数据
|
||
- LRU淘汰策略:自动淘汰最少使用的数据
|
||
- 智能预热:启动时预加载高频数据
|
||
- 统计信息:命中率、淘汰率等监控数据
|
||
"""
|
||
|
||
import asyncio
|
||
import time
|
||
from collections import OrderedDict
|
||
from collections.abc import Callable
|
||
from dataclasses import dataclass
|
||
from typing import Any, Generic, TypeVar
|
||
|
||
from src.common.logger import get_logger
|
||
from src.common.memory_utils import estimate_size_smart
|
||
|
||
logger = get_logger("cache_manager")
|
||
|
||
T = TypeVar("T")
|
||
|
||
|
||
@dataclass
|
||
class CacheEntry(Generic[T]):
|
||
"""缓存条目
|
||
|
||
Attributes:
|
||
value: 缓存的值
|
||
created_at: 创建时间戳
|
||
last_accessed: 最后访问时间戳
|
||
access_count: 访问次数
|
||
size: 数据大小(字节)
|
||
"""
|
||
value: T
|
||
created_at: float
|
||
last_accessed: float
|
||
access_count: int = 0
|
||
size: int = 0
|
||
|
||
|
||
@dataclass
|
||
class CacheStats:
|
||
"""缓存统计信息
|
||
|
||
Attributes:
|
||
hits: 命中次数
|
||
misses: 未命中次数
|
||
evictions: 淘汰次数
|
||
total_size: 总大小(字节)
|
||
item_count: 条目数量
|
||
"""
|
||
hits: int = 0
|
||
misses: int = 0
|
||
evictions: int = 0
|
||
total_size: int = 0
|
||
item_count: int = 0
|
||
|
||
@property
|
||
def hit_rate(self) -> float:
|
||
"""命中率"""
|
||
total = self.hits + self.misses
|
||
return self.hits / total if total > 0 else 0.0
|
||
|
||
@property
|
||
def eviction_rate(self) -> float:
|
||
"""淘汰率"""
|
||
return self.evictions / self.item_count if self.item_count > 0 else 0.0
|
||
|
||
|
||
class LRUCache(Generic[T]):
|
||
"""LRU缓存实现
|
||
|
||
使用OrderedDict实现O(1)的get/set操作
|
||
"""
|
||
|
||
def __init__(
|
||
self,
|
||
max_size: int,
|
||
ttl: float,
|
||
name: str = "cache",
|
||
):
|
||
"""初始化LRU缓存
|
||
|
||
Args:
|
||
max_size: 最大缓存条目数
|
||
ttl: 过期时间(秒)
|
||
name: 缓存名称,用于日志
|
||
"""
|
||
self.max_size = max_size
|
||
self.ttl = ttl
|
||
self.name = name
|
||
self._cache: OrderedDict[str, CacheEntry[T]] = OrderedDict()
|
||
self._lock = asyncio.Lock()
|
||
self._stats = CacheStats()
|
||
|
||
async def get(self, key: str) -> T | None:
|
||
"""获取缓存值
|
||
|
||
Args:
|
||
key: 缓存键
|
||
|
||
Returns:
|
||
缓存值,如果不存在或已过期返回None
|
||
"""
|
||
async with self._lock:
|
||
entry = self._cache.get(key)
|
||
|
||
if entry is None:
|
||
self._stats.misses += 1
|
||
return None
|
||
|
||
# 检查是否过期
|
||
now = time.time()
|
||
if now - entry.created_at > self.ttl:
|
||
# 过期,删除条目
|
||
del self._cache[key]
|
||
self._stats.misses += 1
|
||
self._stats.evictions += 1
|
||
self._stats.item_count -= 1
|
||
self._stats.total_size -= entry.size
|
||
return None
|
||
|
||
# 命中,更新访问信息
|
||
entry.last_accessed = now
|
||
entry.access_count += 1
|
||
self._stats.hits += 1
|
||
|
||
# 移到末尾(最近使用)
|
||
self._cache.move_to_end(key)
|
||
|
||
return entry.value
|
||
|
||
async def set(
|
||
self,
|
||
key: str,
|
||
value: T,
|
||
size: int | None = None,
|
||
ttl: float | None = None,
|
||
) -> None:
|
||
"""设置缓存值
|
||
|
||
Args:
|
||
key: 缓存键
|
||
value: 缓存值
|
||
size: 数据大小(字节),如果为None则尝试估算
|
||
ttl: 自定义过期时间(秒),如果为None则使用默认TTL
|
||
"""
|
||
async with self._lock:
|
||
now = time.time()
|
||
|
||
# 如果键已存在,更新值
|
||
if key in self._cache:
|
||
old_entry = self._cache[key]
|
||
self._stats.total_size -= old_entry.size
|
||
|
||
# 估算大小
|
||
if size is None:
|
||
size = self._estimate_size(value)
|
||
|
||
# 创建新条目(如果指定了ttl,则修改created_at来实现自定义TTL)
|
||
# 通过调整created_at,使得: now - created_at + custom_ttl = self.ttl
|
||
# 即: created_at = now - (self.ttl - custom_ttl)
|
||
if ttl is not None and ttl != self.ttl:
|
||
# 调整创建时间以实现自定义TTL
|
||
adjusted_created_at = now - (self.ttl - ttl)
|
||
logger.debug(
|
||
f"[{self.name}] 使用自定义TTL {ttl}s (默认{self.ttl}s) for key: {key}"
|
||
)
|
||
else:
|
||
adjusted_created_at = now
|
||
|
||
entry = CacheEntry(
|
||
value=value,
|
||
created_at=adjusted_created_at,
|
||
last_accessed=now,
|
||
access_count=0,
|
||
size=size,
|
||
)
|
||
|
||
# 如果缓存已满,淘汰最久未使用的条目
|
||
while len(self._cache) >= self.max_size:
|
||
oldest_key, oldest_entry = self._cache.popitem(last=False)
|
||
self._stats.evictions += 1
|
||
self._stats.item_count -= 1
|
||
self._stats.total_size -= oldest_entry.size
|
||
logger.debug(
|
||
f"[{self.name}] 淘汰缓存条目: {oldest_key} "
|
||
f"(访问{oldest_entry.access_count}次)"
|
||
)
|
||
|
||
# 添加新条目
|
||
self._cache[key] = entry
|
||
self._stats.item_count += 1
|
||
self._stats.total_size += size
|
||
|
||
async def delete(self, key: str) -> bool:
|
||
"""删除缓存条目
|
||
|
||
Args:
|
||
key: 缓存键
|
||
|
||
Returns:
|
||
是否成功删除
|
||
"""
|
||
async with self._lock:
|
||
entry = self._cache.pop(key, None)
|
||
if entry:
|
||
self._stats.item_count -= 1
|
||
self._stats.total_size -= entry.size
|
||
return True
|
||
return False
|
||
|
||
async def clear(self) -> None:
|
||
"""清空缓存"""
|
||
async with self._lock:
|
||
self._cache.clear()
|
||
self._stats = CacheStats()
|
||
|
||
async def get_stats(self) -> CacheStats:
|
||
"""获取统计信息"""
|
||
async with self._lock:
|
||
return CacheStats(
|
||
hits=self._stats.hits,
|
||
misses=self._stats.misses,
|
||
evictions=self._stats.evictions,
|
||
total_size=self._stats.total_size,
|
||
item_count=self._stats.item_count,
|
||
)
|
||
|
||
def _estimate_size(self, value: Any) -> int:
|
||
"""估算数据大小(字节)- 使用准确的估算方法
|
||
|
||
使用深度递归估算,比 sys.getsizeof() 更准确
|
||
"""
|
||
try:
|
||
return estimate_size_smart(value)
|
||
except (TypeError, AttributeError):
|
||
# 无法获取大小,返回默认值
|
||
return 1024
|
||
|
||
|
||
class MultiLevelCache:
|
||
"""多级缓存管理器
|
||
|
||
实现两级缓存架构:
|
||
- L1: 高速缓存,小容量,短TTL
|
||
- L2: 扩展缓存,大容量,长TTL
|
||
|
||
查询时先查L1,未命中再查L2,未命中再从数据源加载
|
||
"""
|
||
|
||
def __init__(
|
||
self,
|
||
l1_max_size: int = 1000,
|
||
l1_ttl: float = 60,
|
||
l2_max_size: int = 10000,
|
||
l2_ttl: float = 300,
|
||
max_memory_mb: int = 100,
|
||
max_item_size_mb: int = 1,
|
||
):
|
||
"""初始化多级缓存
|
||
|
||
Args:
|
||
l1_max_size: L1缓存最大条目数
|
||
l1_ttl: L1缓存TTL(秒)
|
||
l2_max_size: L2缓存最大条目数
|
||
l2_ttl: L2缓存TTL(秒)
|
||
max_memory_mb: 最大内存占用(MB)
|
||
max_item_size_mb: 单个缓存条目最大大小(MB)
|
||
"""
|
||
self.l1_cache: LRUCache[Any] = LRUCache(l1_max_size, l1_ttl, "L1")
|
||
self.l2_cache: LRUCache[Any] = LRUCache(l2_max_size, l2_ttl, "L2")
|
||
self.max_memory_bytes = max_memory_mb * 1024 * 1024
|
||
self.max_item_size_bytes = max_item_size_mb * 1024 * 1024
|
||
self._cleanup_task: asyncio.Task | None = None
|
||
self._is_closing = False # 🔧 添加关闭标志
|
||
|
||
logger.info(
|
||
f"多级缓存初始化: L1({l1_max_size}项/{l1_ttl}s) "
|
||
f"L2({l2_max_size}项/{l2_ttl}s) 内存上限({max_memory_mb}MB) "
|
||
f"单项上限({max_item_size_mb}MB)"
|
||
)
|
||
|
||
async def get(
|
||
self,
|
||
key: str,
|
||
loader: Callable[[], Any] | None = None,
|
||
) -> Any | None:
|
||
"""从缓存获取数据
|
||
|
||
查询顺序:L1 -> L2 -> loader
|
||
|
||
Args:
|
||
key: 缓存键
|
||
loader: 数据加载函数,当缓存未命中时调用
|
||
|
||
Returns:
|
||
缓存值或加载的值,如果都不存在返回None
|
||
"""
|
||
# 1. 尝试从L1获取
|
||
value = await self.l1_cache.get(key)
|
||
if value is not None:
|
||
logger.debug(f"L1缓存命中: {key}")
|
||
return value
|
||
|
||
# 2. 尝试从L2获取
|
||
value = await self.l2_cache.get(key)
|
||
if value is not None:
|
||
logger.debug(f"L2缓存命中: {key}")
|
||
# 提升到L1
|
||
await self.l1_cache.set(key, value)
|
||
return value
|
||
|
||
# 3. 使用loader加载
|
||
if loader is not None:
|
||
logger.debug(f"缓存未命中,从数据源加载: {key}")
|
||
value = await loader() if asyncio.iscoroutinefunction(loader) else loader()
|
||
if value is not None:
|
||
# 同时写入L1和L2
|
||
await self.set(key, value)
|
||
return value
|
||
|
||
return None
|
||
|
||
async def set(
|
||
self,
|
||
key: str,
|
||
value: Any,
|
||
size: int | None = None,
|
||
ttl: float | None = None,
|
||
) -> None:
|
||
"""设置缓存值
|
||
|
||
同时写入L1和L2
|
||
|
||
Args:
|
||
key: 缓存键
|
||
value: 缓存值
|
||
size: 数据大小(字节)
|
||
ttl: 自定义过期时间(秒),如果为None则使用默认TTL
|
||
"""
|
||
# 估算数据大小(如果未提供)
|
||
if size is None:
|
||
size = estimate_size_smart(value)
|
||
|
||
# 检查单个条目大小是否超过限制
|
||
if size > self.max_item_size_bytes:
|
||
logger.warning(
|
||
f"缓存条目过大,跳过缓存: key={key}, "
|
||
f"size={size / (1024 * 1024):.2f}MB, "
|
||
f"limit={self.max_item_size_bytes / (1024 * 1024):.2f}MB"
|
||
)
|
||
return
|
||
|
||
# 根据TTL决定写入哪个缓存层
|
||
if ttl is not None:
|
||
# 有自定义TTL,根据TTL大小决定写入层级
|
||
if ttl <= self.l1_cache.ttl:
|
||
# 短TTL,只写入L1
|
||
await self.l1_cache.set(key, value, size, ttl)
|
||
elif ttl <= self.l2_cache.ttl:
|
||
# 中等TTL,写入L1和L2
|
||
await self.l1_cache.set(key, value, size, ttl)
|
||
await self.l2_cache.set(key, value, size, ttl)
|
||
else:
|
||
# 长TTL,只写入L2
|
||
await self.l2_cache.set(key, value, size, ttl)
|
||
else:
|
||
# 没有自定义TTL,使用默认行为(同时写入L1和L2)
|
||
await self.l1_cache.set(key, value, size)
|
||
await self.l2_cache.set(key, value, size)
|
||
|
||
async def delete(self, key: str) -> None:
|
||
"""删除缓存条目
|
||
|
||
同时从L1和L2删除
|
||
|
||
Args:
|
||
key: 缓存键
|
||
"""
|
||
await self.l1_cache.delete(key)
|
||
await self.l2_cache.delete(key)
|
||
|
||
async def clear(self) -> None:
|
||
"""清空所有缓存"""
|
||
await self.l1_cache.clear()
|
||
await self.l2_cache.clear()
|
||
logger.info("所有缓存已清空")
|
||
|
||
async def get_stats(self) -> dict[str, Any]:
|
||
"""获取所有缓存层的统计信息(修正版,避免重复计数)"""
|
||
l1_stats = await self.l1_cache.get_stats()
|
||
l2_stats = await self.l2_cache.get_stats()
|
||
|
||
# 🔧 修复:计算实际独占的内存,避免L1和L2共享数据的重复计数
|
||
l1_keys = set(self.l1_cache._cache.keys())
|
||
l2_keys = set(self.l2_cache._cache.keys())
|
||
|
||
shared_keys = l1_keys & l2_keys
|
||
l1_only_keys = l1_keys - l2_keys
|
||
l2_only_keys = l2_keys - l1_keys
|
||
|
||
# 计算实际总内存(避免重复计数)
|
||
# L1独占内存
|
||
l1_only_size = sum(
|
||
self.l1_cache._cache[k].size
|
||
for k in l1_only_keys
|
||
if k in self.l1_cache._cache
|
||
)
|
||
# L2独占内存
|
||
l2_only_size = sum(
|
||
self.l2_cache._cache[k].size
|
||
for k in l2_only_keys
|
||
if k in self.l2_cache._cache
|
||
)
|
||
# 共享内存(只计算一次,使用L1的数据)
|
||
shared_size = sum(
|
||
self.l1_cache._cache[k].size
|
||
for k in shared_keys
|
||
if k in self.l1_cache._cache
|
||
)
|
||
|
||
actual_total_size = l1_only_size + l2_only_size + shared_size
|
||
|
||
return {
|
||
"l1": l1_stats,
|
||
"l2": l2_stats,
|
||
"total_memory_mb": actual_total_size / (1024 * 1024),
|
||
"l1_only_mb": l1_only_size / (1024 * 1024),
|
||
"l2_only_mb": l2_only_size / (1024 * 1024),
|
||
"shared_mb": shared_size / (1024 * 1024),
|
||
"shared_keys_count": len(shared_keys),
|
||
"dedup_savings_mb": (l1_stats.total_size + l2_stats.total_size - actual_total_size) / (1024 * 1024),
|
||
"max_memory_mb": self.max_memory_bytes / (1024 * 1024),
|
||
"memory_usage_percent": (actual_total_size / self.max_memory_bytes * 100) if self.max_memory_bytes > 0 else 0,
|
||
}
|
||
|
||
async def check_memory_limit(self) -> None:
|
||
"""检查并强制清理超出内存限制的缓存"""
|
||
stats = await self.get_stats()
|
||
total_size = stats["l1"].total_size + stats["l2"].total_size
|
||
|
||
if total_size > self.max_memory_bytes:
|
||
memory_mb = total_size / (1024 * 1024)
|
||
max_mb = self.max_memory_bytes / (1024 * 1024)
|
||
logger.warning(
|
||
f"缓存内存超限: {memory_mb:.2f}MB / {max_mb:.2f}MB "
|
||
f"({stats['memory_usage_percent']:.1f}%),开始强制清理L2缓存"
|
||
)
|
||
# 优先清理L2缓存(温数据)
|
||
await self.l2_cache.clear()
|
||
|
||
# 如果清理L2后仍超限,清理L1
|
||
stats_after_l2 = await self.get_stats()
|
||
total_after_l2 = stats_after_l2["l1"].total_size + stats_after_l2["l2"].total_size
|
||
if total_after_l2 > self.max_memory_bytes:
|
||
logger.warning("清理L2后仍超限,继续清理L1缓存")
|
||
await self.l1_cache.clear()
|
||
|
||
logger.info("缓存强制清理完成")
|
||
|
||
async def start_cleanup_task(self, interval: float = 60) -> None:
|
||
"""启动定期清理任务
|
||
|
||
Args:
|
||
interval: 清理间隔(秒)
|
||
"""
|
||
if self._cleanup_task is not None:
|
||
logger.warning("清理任务已在运行")
|
||
return
|
||
|
||
async def cleanup_loop():
|
||
while not self._is_closing:
|
||
try:
|
||
await asyncio.sleep(interval)
|
||
|
||
if self._is_closing:
|
||
break
|
||
|
||
stats = await self.get_stats()
|
||
l1_stats = stats["l1"]
|
||
l2_stats = stats["l2"]
|
||
logger.info(
|
||
f"缓存统计 - L1: {l1_stats.item_count}项, "
|
||
f"命中率{l1_stats.hit_rate:.2%} | "
|
||
f"L2: {l2_stats.item_count}项, "
|
||
f"命中率{l2_stats.hit_rate:.2%} | "
|
||
f"内存: {stats['total_memory_mb']:.2f}MB/{stats['max_memory_mb']:.2f}MB "
|
||
f"({stats['memory_usage_percent']:.1f}%) | "
|
||
f"共享: {stats['shared_keys_count']}键/{stats['shared_mb']:.2f}MB "
|
||
f"(去重节省{stats['dedup_savings_mb']:.2f}MB)"
|
||
)
|
||
|
||
# 🔧 清理过期条目
|
||
await self._clean_expired_entries()
|
||
|
||
# 检查内存限制
|
||
await self.check_memory_limit()
|
||
|
||
except asyncio.CancelledError:
|
||
break
|
||
except Exception as e:
|
||
logger.error(f"清理任务异常: {e}", exc_info=True)
|
||
|
||
self._cleanup_task = asyncio.create_task(cleanup_loop())
|
||
logger.info(f"缓存清理任务已启动,间隔{interval}秒")
|
||
|
||
async def stop_cleanup_task(self) -> None:
|
||
"""停止清理任务"""
|
||
self._is_closing = True
|
||
|
||
if self._cleanup_task is not None:
|
||
self._cleanup_task.cancel()
|
||
try:
|
||
await self._cleanup_task
|
||
except asyncio.CancelledError:
|
||
pass
|
||
self._cleanup_task = None
|
||
logger.info("缓存清理任务已停止")
|
||
|
||
async def _clean_expired_entries(self) -> None:
|
||
"""清理过期的缓存条目"""
|
||
try:
|
||
current_time = time.time()
|
||
|
||
# 清理 L1 过期条目
|
||
async with self.l1_cache._lock:
|
||
expired_keys = [
|
||
key for key, entry in self.l1_cache._cache.items()
|
||
if current_time - entry.created_at > self.l1_cache.ttl
|
||
]
|
||
|
||
for key in expired_keys:
|
||
entry = self.l1_cache._cache.pop(key, None)
|
||
if entry:
|
||
self.l1_cache._stats.evictions += 1
|
||
self.l1_cache._stats.item_count -= 1
|
||
self.l1_cache._stats.total_size -= entry.size
|
||
|
||
# 清理 L2 过期条目
|
||
async with self.l2_cache._lock:
|
||
expired_keys = [
|
||
key for key, entry in self.l2_cache._cache.items()
|
||
if current_time - entry.created_at > self.l2_cache.ttl
|
||
]
|
||
|
||
for key in expired_keys:
|
||
entry = self.l2_cache._cache.pop(key, None)
|
||
if entry:
|
||
self.l2_cache._stats.evictions += 1
|
||
self.l2_cache._stats.item_count -= 1
|
||
self.l2_cache._stats.total_size -= entry.size
|
||
|
||
if expired_keys:
|
||
logger.debug(f"清理了 {len(expired_keys)} 个过期缓存条目")
|
||
|
||
except Exception as e:
|
||
logger.error(f"清理过期条目失败: {e}", exc_info=True)
|
||
|
||
|
||
# 全局缓存实例
|
||
_global_cache: MultiLevelCache | None = None
|
||
_cache_lock = asyncio.Lock()
|
||
|
||
|
||
async def get_cache() -> MultiLevelCache:
|
||
"""获取全局缓存实例(单例)
|
||
|
||
从配置文件读取缓存参数,如果配置未加载则使用默认值
|
||
如果配置中禁用了缓存,返回一个最小化的缓存实例(容量为1)
|
||
"""
|
||
global _global_cache
|
||
|
||
if _global_cache is None:
|
||
async with _cache_lock:
|
||
if _global_cache is None:
|
||
# 尝试从配置读取参数
|
||
try:
|
||
from src.config.config import global_config
|
||
|
||
db_config = global_config.database
|
||
|
||
# 检查是否启用缓存
|
||
if not db_config.enable_database_cache:
|
||
logger.info("数据库缓存已禁用,使用最小化缓存实例")
|
||
_global_cache = MultiLevelCache(
|
||
l1_max_size=1,
|
||
l1_ttl=1,
|
||
l2_max_size=1,
|
||
l2_ttl=1,
|
||
max_memory_mb=1,
|
||
)
|
||
return _global_cache
|
||
|
||
l1_max_size = db_config.cache_l1_max_size
|
||
l1_ttl = db_config.cache_l1_ttl
|
||
l2_max_size = db_config.cache_l2_max_size
|
||
l2_ttl = db_config.cache_l2_ttl
|
||
max_memory_mb = db_config.cache_max_memory_mb
|
||
max_item_size_mb = db_config.cache_max_item_size_mb
|
||
cleanup_interval = db_config.cache_cleanup_interval
|
||
|
||
logger.info(
|
||
f"从配置加载缓存参数: L1({l1_max_size}/{l1_ttl}s), "
|
||
f"L2({l2_max_size}/{l2_ttl}s), 内存限制({max_memory_mb}MB), "
|
||
f"单项限制({max_item_size_mb}MB)"
|
||
)
|
||
except Exception as e:
|
||
# 配置未加载,使用默认值
|
||
logger.warning(f"无法从配置加载缓存参数,使用默认值: {e}")
|
||
l1_max_size = 1000
|
||
l1_ttl = 60
|
||
l2_max_size = 10000
|
||
l2_ttl = 300
|
||
max_memory_mb = 100
|
||
max_item_size_mb = 1
|
||
cleanup_interval = 60
|
||
|
||
_global_cache = MultiLevelCache(
|
||
l1_max_size=l1_max_size,
|
||
l1_ttl=l1_ttl,
|
||
l2_max_size=l2_max_size,
|
||
l2_ttl=l2_ttl,
|
||
max_memory_mb=max_memory_mb,
|
||
max_item_size_mb=max_item_size_mb,
|
||
)
|
||
await _global_cache.start_cleanup_task(interval=cleanup_interval)
|
||
|
||
return _global_cache
|
||
|
||
|
||
async def close_cache() -> None:
|
||
"""关闭全局缓存"""
|
||
global _global_cache
|
||
|
||
if _global_cache is not None:
|
||
await _global_cache.stop_cleanup_task()
|
||
await _global_cache.clear()
|
||
_global_cache = None
|
||
logger.info("全局缓存已关闭")
|