Files
crawl4ai/crawl4ai/async_dispatcher.py
UncleCode 1630fbdafe feat(monitor): add real-time crawler monitoring system with memory management
Implements a comprehensive monitoring and visualization system for tracking web crawler operations in real-time. The system includes:
- Terminal-based dashboard with rich UI for displaying task statuses
- Memory pressure monitoring and adaptive dispatch control
- Queue statistics and performance metrics tracking
- Detailed task progress visualization
- Stress testing framework for memory management

This addition helps operators track crawler performance and manage memory usage more effectively.
2025-03-12 19:05:24 +08:00

646 lines
25 KiB
Python

from typing import Dict, Optional, List, Tuple
from .async_configs import CrawlerRunConfig
from .models import (
CrawlResult,
CrawlerTaskResult,
CrawlStatus,
DomainState,
)
from .components.crawler_monitor import CrawlerMonitor
from .types import AsyncWebCrawler
from collections.abc import AsyncGenerator
import time
import psutil
import asyncio
import uuid
from urllib.parse import urlparse
import random
from abc import ABC, abstractmethod
class RateLimiter:
def __init__(
self,
base_delay: Tuple[float, float] = (1.0, 3.0),
max_delay: float = 60.0,
max_retries: int = 3,
rate_limit_codes: List[int] = None,
):
self.base_delay = base_delay
self.max_delay = max_delay
self.max_retries = max_retries
self.rate_limit_codes = rate_limit_codes or [429, 503]
self.domains: Dict[str, DomainState] = {}
def get_domain(self, url: str) -> str:
return urlparse(url).netloc
async def wait_if_needed(self, url: str) -> None:
domain = self.get_domain(url)
state = self.domains.get(domain)
if not state:
self.domains[domain] = DomainState()
state = self.domains[domain]
now = time.time()
if state.last_request_time:
wait_time = max(0, state.current_delay - (now - state.last_request_time))
if wait_time > 0:
await asyncio.sleep(wait_time)
# Random delay within base range if no current delay
if state.current_delay == 0:
state.current_delay = random.uniform(*self.base_delay)
state.last_request_time = time.time()
def update_delay(self, url: str, status_code: int) -> bool:
domain = self.get_domain(url)
state = self.domains[domain]
if status_code in self.rate_limit_codes:
state.fail_count += 1
if state.fail_count > self.max_retries:
return False
# Exponential backoff with random jitter
state.current_delay = min(
state.current_delay * 2 * random.uniform(0.75, 1.25), self.max_delay
)
else:
# Gradually reduce delay on success
state.current_delay = max(
random.uniform(*self.base_delay), state.current_delay * 0.75
)
state.fail_count = 0
return True
class BaseDispatcher(ABC):
def __init__(
self,
rate_limiter: Optional[RateLimiter] = None,
monitor: Optional[CrawlerMonitor] = None,
):
self.crawler = None
self._domain_last_hit: Dict[str, float] = {}
self.concurrent_sessions = 0
self.rate_limiter = rate_limiter
self.monitor = monitor
@abstractmethod
async def crawl_url(
self,
url: str,
config: CrawlerRunConfig,
task_id: str,
monitor: Optional[CrawlerMonitor] = None,
) -> CrawlerTaskResult:
pass
@abstractmethod
async def run_urls(
self,
urls: List[str],
crawler: AsyncWebCrawler, # noqa: F821
config: CrawlerRunConfig,
monitor: Optional[CrawlerMonitor] = None,
) -> List[CrawlerTaskResult]:
pass
class MemoryAdaptiveDispatcher(BaseDispatcher):
def __init__(
self,
memory_threshold_percent: float = 90.0,
critical_threshold_percent: float = 95.0, # New critical threshold
recovery_threshold_percent: float = 85.0, # New recovery threshold
check_interval: float = 1.0,
max_session_permit: int = 20,
fairness_timeout: float = 600.0, # 10 minutes before prioritizing long-waiting URLs
rate_limiter: Optional[RateLimiter] = None,
monitor: Optional[CrawlerMonitor] = None,
):
super().__init__(rate_limiter, monitor)
self.memory_threshold_percent = memory_threshold_percent
self.critical_threshold_percent = critical_threshold_percent
self.recovery_threshold_percent = recovery_threshold_percent
self.check_interval = check_interval
self.max_session_permit = max_session_permit
self.fairness_timeout = fairness_timeout
self.result_queue = asyncio.Queue()
self.task_queue = asyncio.PriorityQueue() # Priority queue for better management
self.memory_pressure_mode = False # Flag to indicate when we're in memory pressure mode
self.current_memory_percent = 0.0 # Track current memory usage
async def _memory_monitor_task(self):
"""Background task to continuously monitor memory usage and update state"""
while True:
self.current_memory_percent = psutil.virtual_memory().percent
# Enter memory pressure mode if we cross the threshold
if not self.memory_pressure_mode and self.current_memory_percent >= self.memory_threshold_percent:
self.memory_pressure_mode = True
if self.monitor:
self.monitor.update_memory_status("PRESSURE")
# Exit memory pressure mode if we go below recovery threshold
elif self.memory_pressure_mode and self.current_memory_percent <= self.recovery_threshold_percent:
self.memory_pressure_mode = False
if self.monitor:
self.monitor.update_memory_status("NORMAL")
# In critical mode, we might need to take more drastic action
if self.current_memory_percent >= self.critical_threshold_percent:
if self.monitor:
self.monitor.update_memory_status("CRITICAL")
# We could implement additional memory-saving measures here
await asyncio.sleep(self.check_interval)
def _get_priority_score(self, wait_time: float, retry_count: int) -> float:
"""Calculate priority score (lower is higher priority)
- URLs waiting longer than fairness_timeout get higher priority
- More retry attempts decreases priority
"""
if wait_time > self.fairness_timeout:
# High priority for long-waiting URLs
return -wait_time
# Standard priority based on retries
return retry_count
async def crawl_url(
self,
url: str,
config: CrawlerRunConfig,
task_id: str,
retry_count: int = 0,
) -> CrawlerTaskResult:
start_time = time.time()
error_message = ""
memory_usage = peak_memory = 0.0
# Get starting memory for accurate measurement
process = psutil.Process()
start_memory = process.memory_info().rss / (1024 * 1024)
try:
if self.monitor:
self.monitor.update_task(
task_id,
status=CrawlStatus.IN_PROGRESS,
start_time=start_time,
retry_count=retry_count
)
self.concurrent_sessions += 1
if self.rate_limiter:
await self.rate_limiter.wait_if_needed(url)
# Check if we're in critical memory state
if self.current_memory_percent >= self.critical_threshold_percent:
# Requeue this task with increased priority and retry count
enqueue_time = time.time()
priority = self._get_priority_score(enqueue_time - start_time, retry_count + 1)
await self.task_queue.put((priority, (url, task_id, retry_count + 1, enqueue_time)))
# Update monitoring
if self.monitor:
self.monitor.update_task(
task_id,
status=CrawlStatus.QUEUED,
error_message="Requeued due to critical memory pressure"
)
# Return placeholder result with requeued status
return CrawlerTaskResult(
task_id=task_id,
url=url,
result=CrawlResult(
url=url, html="", metadata={"status": "requeued"},
success=False, error_message="Requeued due to critical memory pressure"
),
memory_usage=0,
peak_memory=0,
start_time=start_time,
end_time=time.time(),
error_message="Requeued due to critical memory pressure",
retry_count=retry_count + 1
)
# Execute the crawl
result = await self.crawler.arun(url, config=config, session_id=task_id)
# Measure memory usage
end_memory = process.memory_info().rss / (1024 * 1024)
memory_usage = peak_memory = end_memory - start_memory
# Handle rate limiting
if self.rate_limiter and result.status_code:
if not self.rate_limiter.update_delay(url, result.status_code):
error_message = f"Rate limit retry count exceeded for domain {urlparse(url).netloc}"
if self.monitor:
self.monitor.update_task(task_id, status=CrawlStatus.FAILED)
# Update status based on result
if not result.success:
error_message = result.error_message
if self.monitor:
self.monitor.update_task(task_id, status=CrawlStatus.FAILED)
elif self.monitor:
self.monitor.update_task(task_id, status=CrawlStatus.COMPLETED)
except Exception as e:
error_message = str(e)
if self.monitor:
self.monitor.update_task(task_id, status=CrawlStatus.FAILED)
result = CrawlResult(
url=url, html="", metadata={}, success=False, error_message=str(e)
)
finally:
end_time = time.time()
if self.monitor:
self.monitor.update_task(
task_id,
end_time=end_time,
memory_usage=memory_usage,
peak_memory=peak_memory,
error_message=error_message,
retry_count=retry_count
)
self.concurrent_sessions -= 1
return CrawlerTaskResult(
task_id=task_id,
url=url,
result=result,
memory_usage=memory_usage,
peak_memory=peak_memory,
start_time=start_time,
end_time=end_time,
error_message=error_message,
retry_count=retry_count
)
async def run_urls(
self,
urls: List[str],
crawler: AsyncWebCrawler,
config: CrawlerRunConfig,
) -> List[CrawlerTaskResult]:
self.crawler = crawler
# Start the memory monitor task
memory_monitor = asyncio.create_task(self._memory_monitor_task())
if self.monitor:
self.monitor.start()
results = []
try:
# Initialize task queue
for url in urls:
task_id = str(uuid.uuid4())
if self.monitor:
self.monitor.add_task(task_id, url)
# Add to queue with initial priority 0, retry count 0, and current time
await self.task_queue.put((0, (url, task_id, 0, time.time())))
active_tasks = []
# Process until both queues are empty
while not self.task_queue.empty() or active_tasks:
# If memory pressure is low, start new tasks
if not self.memory_pressure_mode and len(active_tasks) < self.max_session_permit:
try:
# Try to get a task with timeout to avoid blocking indefinitely
priority, (url, task_id, retry_count, enqueue_time) = await asyncio.wait_for(
self.task_queue.get(), timeout=0.1
)
# Create and start the task
task = asyncio.create_task(
self.crawl_url(url, config, task_id, retry_count)
)
active_tasks.append(task)
# Update waiting time in monitor
if self.monitor:
wait_time = time.time() - enqueue_time
self.monitor.update_task(
task_id,
wait_time=wait_time,
status=CrawlStatus.IN_PROGRESS
)
except asyncio.TimeoutError:
# No tasks in queue, that's fine
pass
# Wait for completion even if queue is starved
if active_tasks:
done, pending = await asyncio.wait(
active_tasks, timeout=0.1, return_when=asyncio.FIRST_COMPLETED
)
# Process completed tasks
for completed_task in done:
result = await completed_task
results.append(result)
# Update active tasks list
active_tasks = list(pending)
else:
# If no active tasks but still waiting, sleep briefly
await asyncio.sleep(self.check_interval / 2)
# Update priorities for waiting tasks if needed
await self._update_queue_priorities()
return results
except Exception as e:
if self.monitor:
self.monitor.update_memory_status(f"QUEUE_ERROR: {str(e)}")
finally:
# Clean up
memory_monitor.cancel()
if self.monitor:
self.monitor.stop()
async def _update_queue_priorities(self):
"""Periodically update priorities of items in the queue to prevent starvation"""
# Skip if queue is empty
if self.task_queue.empty():
return
# Use a drain-and-refill approach to update all priorities
temp_items = []
# Drain the queue (with a safety timeout to prevent blocking)
try:
drain_start = time.time()
while not self.task_queue.empty() and time.time() - drain_start < 5.0: # 5 second safety timeout
try:
# Get item from queue with timeout
priority, (url, task_id, retry_count, enqueue_time) = await asyncio.wait_for(
self.task_queue.get(), timeout=0.1
)
# Calculate new priority based on current wait time
current_time = time.time()
wait_time = current_time - enqueue_time
new_priority = self._get_priority_score(wait_time, retry_count)
# Store with updated priority
temp_items.append((new_priority, (url, task_id, retry_count, enqueue_time)))
# Update monitoring stats for this task
if self.monitor and task_id in self.monitor.stats:
self.monitor.update_task(task_id, wait_time=wait_time)
except asyncio.TimeoutError:
# Queue might be empty or very slow
break
except Exception as e:
# If anything goes wrong, make sure we refill the queue with what we've got
self.monitor.update_memory_status(f"QUEUE_ERROR: {str(e)}")
# Calculate queue statistics
if temp_items and self.monitor:
total_queued = len(temp_items)
wait_times = [item[1][3] for item in temp_items]
highest_wait_time = time.time() - min(wait_times) if wait_times else 0
avg_wait_time = sum(time.time() - t for t in wait_times) / len(wait_times) if wait_times else 0
# Update queue statistics in monitor
self.monitor.update_queue_statistics(
total_queued=total_queued,
highest_wait_time=highest_wait_time,
avg_wait_time=avg_wait_time
)
# Sort by priority (lowest number = highest priority)
temp_items.sort(key=lambda x: x[0])
# Refill the queue with updated priorities
for item in temp_items:
await self.task_queue.put(item)
async def run_urls_stream(
self,
urls: List[str],
crawler: AsyncWebCrawler,
config: CrawlerRunConfig,
) -> AsyncGenerator[CrawlerTaskResult, None]:
self.crawler = crawler
# Start the memory monitor task
memory_monitor = asyncio.create_task(self._memory_monitor_task())
if self.monitor:
self.monitor.start()
try:
# Initialize task queue
for url in urls:
task_id = str(uuid.uuid4())
if self.monitor:
self.monitor.add_task(task_id, url)
# Add to queue with initial priority 0, retry count 0, and current time
await self.task_queue.put((0, (url, task_id, 0, time.time())))
active_tasks = []
completed_count = 0
total_urls = len(urls)
while completed_count < total_urls:
# If memory pressure is low, start new tasks
if not self.memory_pressure_mode and len(active_tasks) < self.max_session_permit:
try:
# Try to get a task with timeout
priority, (url, task_id, retry_count, enqueue_time) = await asyncio.wait_for(
self.task_queue.get(), timeout=0.1
)
# Create and start the task
task = asyncio.create_task(
self.crawl_url(url, config, task_id, retry_count)
)
active_tasks.append(task)
# Update waiting time in monitor
if self.monitor:
wait_time = time.time() - enqueue_time
self.monitor.update_task(
task_id,
wait_time=wait_time,
status=CrawlStatus.IN_PROGRESS
)
except asyncio.TimeoutError:
# No tasks in queue, that's fine
pass
# Process completed tasks and yield results
if active_tasks:
done, pending = await asyncio.wait(
active_tasks, timeout=0.1, return_when=asyncio.FIRST_COMPLETED
)
for completed_task in done:
result = await completed_task
# Only count as completed if it wasn't requeued
if "requeued" not in result.error_message:
completed_count += 1
yield result
# Update active tasks list
active_tasks = list(pending)
else:
# If no active tasks but still waiting, sleep briefly
await asyncio.sleep(self.check_interval / 2)
# Update priorities for waiting tasks if needed
await self._update_queue_priorities()
finally:
# Clean up
memory_monitor.cancel()
if self.monitor:
self.monitor.stop()
class SemaphoreDispatcher(BaseDispatcher):
def __init__(
self,
semaphore_count: int = 5,
max_session_permit: int = 20,
rate_limiter: Optional[RateLimiter] = None,
monitor: Optional[CrawlerMonitor] = None,
):
super().__init__(rate_limiter, monitor)
self.semaphore_count = semaphore_count
self.max_session_permit = max_session_permit
async def crawl_url(
self,
url: str,
config: CrawlerRunConfig,
task_id: str,
semaphore: asyncio.Semaphore = None,
) -> CrawlerTaskResult:
start_time = time.time()
error_message = ""
memory_usage = peak_memory = 0.0
try:
if self.monitor:
self.monitor.update_task(
task_id, status=CrawlStatus.IN_PROGRESS, start_time=start_time
)
if self.rate_limiter:
await self.rate_limiter.wait_if_needed(url)
async with semaphore:
process = psutil.Process()
start_memory = process.memory_info().rss / (1024 * 1024)
result = await self.crawler.arun(url, config=config, session_id=task_id)
end_memory = process.memory_info().rss / (1024 * 1024)
memory_usage = peak_memory = end_memory - start_memory
if self.rate_limiter and result.status_code:
if not self.rate_limiter.update_delay(url, result.status_code):
error_message = f"Rate limit retry count exceeded for domain {urlparse(url).netloc}"
if self.monitor:
self.monitor.update_task(task_id, status=CrawlStatus.FAILED)
return CrawlerTaskResult(
task_id=task_id,
url=url,
result=result,
memory_usage=memory_usage,
peak_memory=peak_memory,
start_time=start_time,
end_time=time.time(),
error_message=error_message,
)
if not result.success:
error_message = result.error_message
if self.monitor:
self.monitor.update_task(task_id, status=CrawlStatus.FAILED)
elif self.monitor:
self.monitor.update_task(task_id, status=CrawlStatus.COMPLETED)
except Exception as e:
error_message = str(e)
if self.monitor:
self.monitor.update_task(task_id, status=CrawlStatus.FAILED)
result = CrawlResult(
url=url, html="", metadata={}, success=False, error_message=str(e)
)
finally:
end_time = time.time()
if self.monitor:
self.monitor.update_task(
task_id,
end_time=end_time,
memory_usage=memory_usage,
peak_memory=peak_memory,
error_message=error_message,
)
return CrawlerTaskResult(
task_id=task_id,
url=url,
result=result,
memory_usage=memory_usage,
peak_memory=peak_memory,
start_time=start_time,
end_time=end_time,
error_message=error_message,
)
async def run_urls(
self,
crawler: AsyncWebCrawler, # noqa: F821
urls: List[str],
config: CrawlerRunConfig,
) -> List[CrawlerTaskResult]:
self.crawler = crawler
if self.monitor:
self.monitor.start()
try:
semaphore = asyncio.Semaphore(self.semaphore_count)
tasks = []
for url in urls:
task_id = str(uuid.uuid4())
if self.monitor:
self.monitor.add_task(task_id, url)
task = asyncio.create_task(
self.crawl_url(url, config, task_id, semaphore)
)
tasks.append(task)
return await asyncio.gather(*tasks, return_exceptions=True)
finally:
if self.monitor:
self.monitor.stop()