摘要
本文深入探讨了在容器化(虚拟化)环境中部署与运行智能体工作流时,面临的延迟与吞吐量之间的核心权衡问题。通过构建一个完整的、可运行的示例项目,我们展示了一个智能体工作流引擎在Docker容器环境下的实现。项目重点演示了如何通过一个动态资源调度器,根据工作流负载和SLO(服务水平目标)实时调整容器的CPU与内存限制,从而在低延迟处理与高吞吐批处理之间寻找最优解。文章包含了项目架构、核心代码实现、性能监控方案以及具体的调优实践,为开发者在实际场景中优化智能体系统性能提供了可借鉴的蓝本。
1. 项目概述与设计思路
在基于微服务或函数即服务(FaaS)的智能体系统中,每个智能体(Agent)或其关键组件(如推理引擎、工具执行器)常被部署在独立的虚拟化环境(如容器、微型虚拟机)中。这种隔离带来了安全性、可维护性和弹性伸缩的优势,但也引入了额外的开销,主要体现在:
- 虚拟化层开销:容器引擎(如Docker)、编排器(如Kubernetes)本身消耗的CPU和内存资源。
- 资源限制的副作用:为容器设置的CPU份额(
cpu-shares)和内存上限(memory limit)虽然防止了资源侵占,但在请求突发时,可能因资源不足导致处理延迟增加,甚至因OOM(内存不足)被杀死。 - 网络与I/O虚拟化:容器间的通信、与宿主机或外部服务的I/O可能经过额外的虚拟网络层,增加延迟。
本项目旨在构建一个概念验证系统,模拟智能体工作流在容器化环境中的执行,并实现一个动态资源调度器来调优延迟与吞吐。核心设计思路如下:
- 虚拟化环境抽象层:定义统一的接口来管理"执行单元"(对应一个容器),包括创建、执行任务、获取状态和设置资源限制。这允许我们未来轻松切换底层虚拟化技术(如从Docker切换到
gVisor或Kata Containers)。 - 智能体工作流引擎:负责解析和执行一个简单的多步骤智能体工作流。每个步骤由一个特定的"技能"(Skill)在独立的执行单元中完成。
- 资源调度器:系统的"大脑"。它监控工作流队列长度、任务处理延迟等指标,并根据预设的调优策略(如"偏向低延迟"或"偏向高吞吐")动态调整每个执行单元的资源配额。
- 监控与可视化:集成
Prometheus客户端来暴露关键指标(延迟、吞吐、资源使用率),并可通过Grafana进行可视化,为调优决策提供数据支撑。
通过运行此项目,开发者可以直观地观察到:
- 在严格资源限制下,系统吞吐量受限,但资源利用率高;任务排队导致尾部延迟激增。
- 放宽资源限制可以减少延迟,但可能导致资源闲置,单位资源吞吐下降。
- 动态调度器如何根据实时负载在两者间取得平衡。
2. 项目结构树
agent-virt-tuning/
├── requirements.txt
├── config.yaml
├── scheduler/
│ ├── __init__.py
│ └── dynamic_scheduler.py
├── virtualization/
│ ├── __init__.py
│ ├── base.py
│ └── docker_env.py
├── workflow/
│ ├── __init__.py
│ ├── engine.py
│ └── skills.py
├── monitor/
│ ├── __init__.py
│ └── metrics.py
├── main.py
├── run_workload.py
└── tests/
├── __init__.py
├── test_scheduler.py
└── test_workflow.py
3. 核心代码实现
文件路径: requirements.txt
docker>=6.0.0
pyyaml>=5.4
prometheus-client>=0.17.0
numpy>=1.21.0
pytest>=7.0.0
文件路径: config.yaml
virtualization:
type: "docker" # 未来可扩展为 'gvisor', 'kata'
docker:
base_image: "python:3.9-slim"
network: "agent-network"
workflow:
max_queue_size: 100
default_timeout_seconds: 30
scheduler:
update_interval_seconds: 10
latency_slo_milliseconds: 500 # 延迟服务水平目标
strategy: "balanced" # 可选: latency_first, throughput_first, balanced
resource_adjustment:
cpu_step: 0.2 # 每次调整CPU份额的步长(核心数)
memory_step_mb: 128 # 每次调整内存的步长(MB)
min_cpu: 0.5
max_cpu: 4.0
min_memory_mb: 256
max_memory_mb: 2048
monitoring:
prometheus_port: 8000
文件路径: virtualization/base.py
"""
虚拟化环境抽象基类定义。
"""
from abc import ABC, abstractmethod
from typing import Any, Dict, Optional
from dataclasses import dataclass
@dataclass
class ResourceSpec:
"""资源规格定义"""
cpu_limit: float # CPU核心数
memory_limit_mb: int # 内存限制(MB)
class ExecutionUnit(ABC):
"""执行单元抽象类,代表一个隔离的运行环境(如容器)"""
def __init__(self, unit_id: str, resource_spec: ResourceSpec):
self.unit_id = unit_id
self.resource_spec = resource_spec
self.status = "created" # created, running, stopped, error
@abstractmethod
async def start(self):
"""启动执行单元"""
pass
@abstractmethod
async def execute(self, command: str, input_data: str = "") -> Dict[str, Any]:
"""
在执行单元内执行命令或调用。
返回字典,至少包含 'success', 'output', 'error', 'execution_time_ms' 键。
"""
pass
@abstractmethod
async def update_resources(self, new_spec: ResourceSpec) -> bool:
"""动态更新资源限制"""
pass
@abstractmethod
async def stop(self):
"""停止并清理执行单元"""
pass
class VirtualizationEnv(ABC):
"""虚拟化环境管理器抽象类"""
@abstractmethod
async def create_unit(self, unit_id: str, resource_spec: ResourceSpec, **kwargs) -> ExecutionUnit:
"""创建一个新的执行单元"""
pass
@abstractmethod
async def list_units(self) -> Dict[str, ExecutionUnit]:
"""获取所有执行单元"""
pass
文件路径: virtualization/docker_env.py
"""
基于Docker的虚拟化环境实现。
"""
import docker
import asyncio
from typing import Dict, Any
from .base import VirtualizationEnv, ExecutionUnit, ResourceSpec
from concurrent.futures import ThreadPoolExecutor
class DockerExecutionUnit(ExecutionUnit):
"""Docker容器执行单元"""
def __init__(self, unit_id: str, resource_spec: ResourceSpec, container):
super().__init__(unit_id, resource_spec)
self._container = container
self._docker_client = docker.from_env()
self._thread_pool = ThreadPoolExecutor(max_workers=2)
async def start(self):
loop = asyncio.get_event_loop()
await loop.run_in_executor(self._thread_pool, self._container.start)
self.status = "running"
async def execute(self, command: str, input_data: str = "") -> Dict[str, Any]:
import time
start_time = time.time()
result = {"success": False, "output": "", "error": "", "execution_time_ms": 0}
try:
# 在容器内执行命令。这是一个简化示例,实际中可能需要更复杂的交互。
exec_id = await asyncio.get_event_loop().run_in_executor(
self._thread_pool,
lambda: self._docker_client.api.exec_create(
self._container.id,
cmd=['sh', '-c', f'echo "{input_data[:100]}" | {command}'], # 简单管道模拟输入
stdout=True,
stderr=True
)
)
exec_output = await asyncio.get_event_loop().run_in_executor(
self._thread_pool,
lambda: self._docker_client.api.exec_start(exec_id['Id'], stream=False)
)
exec_inspect = await asyncio.get_event_loop().run_in_executor(
self._thread_pool,
lambda: self._docker_client.api.exec_inspect(exec_id['Id'])
)
result['output'] = exec_output.decode('utf-8') if isinstance(exec_output, bytes) else exec_output
result['success'] = (exec_inspect['ExitCode'] == 0)
if not result['success']:
result['error'] = f"Exit code: {exec_inspect['ExitCode']}"
except Exception as e:
result['error'] = str(e)
result['execution_time_ms'] = int((time.time() - start_time) * 1000)
return result
async def update_resources(self, new_spec: ResourceSpec) -> bool:
try:
# Docker容器资源更新(需要容器在运行状态)
update_config = docker.types.Resources(
cpu_quota=int(new_spec.cpu_limit * 100000), # 将核心数转换为微秒配额
cpu_period=100000,
mem_limit=f"{new_spec.memory_limit_mb}m"
)
await asyncio.get_event_loop().run_in_executor(
self._thread_pool,
lambda: self._container.update(**update_config)
)
self.resource_spec = new_spec
return True
except Exception:
return False
async def stop(self):
try:
await asyncio.get_event_loop().run_in_executor(
self._thread_pool,
lambda: self._container.stop(timeout=5)
)
except Exception:
pass
try:
await asyncio.get_event_loop().run_in_executor(
self._thread_pool,
lambda: self._container.remove()
)
except Exception:
pass
self.status = "stopped"
self._thread_pool.shutdown(wait=False)
class DockerVirtualizationEnv(VirtualizationEnv):
"""Docker环境管理器"""
def __init__(self, config: Dict[str, Any]):
self._client = docker.from_env()
self._config = config
self._units: Dict[str, DockerExecutionUnit] = {}
# 确保网络存在
self._ensure_network()
def _ensure_network(self):
network_name = self._config['docker']['network']
try:
self._client.networks.get(network_name)
except docker.errors.NotFound:
self._client.networks.create(network_name, driver="bridge")
async def create_unit(self, unit_id: str, resource_spec: ResourceSpec, **kwargs) -> DockerExecutionUnit:
# 构建容器创建配置
container_config = {
'image': self._config['docker']['base_image'],
'command': 'tail -f /dev/null', # 保持容器运行
'detach': True,
'name': f'agent-unit-{unit_id}',
'network': self._config['docker']['network'],
'cpu_quota': int(resource_spec.cpu_limit * 100000),
'cpu_period': 100000,
'mem_limit': f'{resource_spec.memory_limit_mb}m',
'environment': ['PYTHONUNBUFFERED=1'],
}
container = await asyncio.get_event_loop().run_in_executor(
None, lambda: self._client.containers.create(**container_config)
)
unit = DockerExecutionUnit(unit_id, resource_spec, container)
self._units[unit_id] = unit
return unit
async def list_units(self) -> Dict[str, DockerExecutionUnit]:
return self._units.copy()
文件路径: workflow/skills.py
"""
定义智能体工作流中可用的技能(Skill)。
每个技能映射到执行单元中的一个命令或调用。
"""
from typing import Dict, Any
class Skill:
def __init__(self, name: str, command: str, estimated_resource: Dict[str, Any]):
self.name = name
self.command = command
self.estimated_resource = estimated_resource # 预估资源消耗,e.g., {'cpu': 0.5, 'memory_mb': 200}
# 预定义的技能库
SKILL_REGISTRY = {
"text_processor": Skill(
name="text_processor",
command="python -c \"import sys; data=sys.stdin.read().strip(); print(f'Processed: {data.upper()} [{len(data)} chars]')\"",
estimated_resource={'cpu': 0.3, 'memory_mb': 150}
),
"ai_inference": Skill(
name="ai_inference",
# 模拟一个轻量级AI推理,实际中会调用模型服务
command="python -c \"import time, sys, random; data=sys.stdin.read(); time.sleep(random.uniform(0.05, 0.2)); print(f'AI Result for <<{data[:20]}...>>: score={random.random():.2f}')\"",
estimated_resource={'cpu': 1.5, 'memory_mb': 800}
),
"data_aggregator": Skill(
name="data_aggregator",
command="python -c \"import sys, json; inputs = [line.strip() for line in sys.stdin if line]; print(f'Aggregated {len(inputs)} items: {inputs[-1][:50]}...')\"",
estimated_resource={'cpu': 0.2, 'memory_mb': 100}
)
}
文件路径: workflow/engine.py
"""
智能体工作流引擎。
负责编排技能在执行单元中的执行顺序。
"""
import asyncio
import uuid
from typing import List, Dict, Any, Optional
from datetime import datetime
from ..virtualization.base import VirtualizationEnv, ExecutionUnit, ResourceSpec
from .skills import SKILL_REGISTRY, Skill
class WorkflowStep:
def __init__(self, skill_name: str, input_data: str = ""):
self.skill_name = skill_name
self.input_data = input_data
self.skill: Optional[Skill] = SKILL_REGISTRY.get(skill_name)
self.result: Optional[Dict[str, Any]] = None
self.execution_unit: Optional[ExecutionUnit] = None
class WorkflowInstance:
"""一个工作流执行实例"""
def __init__(self, wf_id: str, steps: List[WorkflowStep]):
self.id = wf_id
self.steps = steps
self.status = "pending" # pending, running, completed, failed
self.start_time: Optional[datetime] = None
self.end_time: Optional[datetime] = None
self.final_output: Optional[str] = None
class WorkflowEngine:
def __init__(self, virt_env: VirtualizationEnv, max_queue_size: int = 100):
self.virt_env = virt_env
self.max_queue_size = max_queue_size
self.pending_queue: asyncio.Queue[WorkflowInstance] = asyncio.Queue(maxsize=max_queue_size)
self.active_instances: Dict[str, WorkflowInstance] = {}
self._unit_skill_map: Dict[str, str] = {} # unit_id -> skill_name
self._skill_unit_pool: Dict[str, List[ExecutionUnit]] = {} # skill_name -> list of units
self._lock = asyncio.Lock()
async def _ensure_unit_for_skill(self, skill_name: str, resource_spec: ResourceSpec) -> ExecutionUnit:
"""确保某个技能有可用的执行单元,如果没有则创建"""
async with self._lock:
if skill_name not in self._skill_unit_pool:
self._skill_unit_pool[skill_name] = []
pool = self._skill_unit_pool[skill_name]
for unit in pool:
if unit.status == "running":
return unit
# 没有空闲单元,创建新的
unit_id = f"{skill_name}-{uuid.uuid4().hex[:8]}"
unit = await self.virt_env.create_unit(unit_id, resource_spec)
await unit.start()
self._unit_skill_map[unit.unit_id] = skill_name
pool.append(unit)
return unit
async def submit_workflow(self, steps_def: List[Dict[str, Any]]) -> str:
"""提交一个工作流,返回工作流ID"""
if self.pending_queue.full():
raise RuntimeError("Workflow queue is full")
steps = [WorkflowStep(step_def['skill'], step_def.get('input', '')) for step_def in steps_def]
wf_id = f"wf-{uuid.uuid4().hex[:8]}"
instance = WorkflowInstance(wf_id, steps)
await self.pending_queue.put(instance)
self.active_instances[wf_id] = instance
return wf_id
async def _execute_step(self, step: WorkflowStep) -> bool:
"""执行单个步骤"""
if not step.skill:
step.result = {'success': False, 'error': f"Skill '{step.skill_name}' not found"}
return False
# 根据技能预估的资源需求创建或获取执行单元
est = step.skill.estimated_resource
resource_spec = ResourceSpec(
cpu_limit=est['cpu'],
memory_limit_mb=est['memory_mb']
)
try:
unit = await self._ensure_unit_for_skill(step.skill_name, resource_spec)
step.execution_unit = unit
step.result = await unit.execute(step.skill.command, step.input_data)
return step.result['success']
except Exception as e:
step.result = {'success': False, 'error': str(e)}
return False
async def process_workflow(self, instance: WorkflowInstance):
"""处理一个工作流实例"""
instance.status = "running"
instance.start_time = datetime.utcnow()
step_outputs = []
for step in instance.steps:
success = await self._execute_step(step)
step_outputs.append(step.result.get('output', '') if success else f"Error: {step.result.get('error')}")
if not success:
instance.status = "failed"
break
if instance.status == "running":
instance.status = "completed"
instance.final_output = " | ".join(step_outputs)
instance.end_time = datetime.utcnow()
# 从活跃实例中移除
self.active_instances.pop(instance.id, None)
async def run(self):
"""启动工作流引擎处理循环"""
print("Workflow engine started.")
while True:
try:
instance = await self.pending_queue.get()
asyncio.create_task(self.process_workflow(instance))
except asyncio.CancelledError:
break
except Exception as e:
print(f"Error processing workflow from queue: {e}")
文件路径: scheduler/dynamic_scheduler.py
"""
动态资源调度器。
根据监控指标调整执行单元的资源限制。
"""
import asyncio
import time
from typing import Dict, Any, List
from dataclasses import dataclass
from ..virtualization.base import VirtualizationEnv, ResourceSpec
from ..workflow.engine import WorkflowEngine
from ..monitor.metrics import workflow_latency_histogram, workflow_throughput_counter, resource_usage_gauge
@dataclass
class SchedulerMetrics:
avg_latency_ms: float
throughput_per_min: float
queue_length: int
unit_resources: Dict[str, ResourceSpec] # unit_id -> current resource
class DynamicResourceScheduler:
def __init__(self, virt_env: VirtualizationEnv, workflow_engine: WorkflowEngine, config: Dict[str, Any]):
self.virt_env = virt_env
self.engine = workflow_engine
self.config = config['scheduler']
self.metrics_history: List[SchedulerMetrics] = []
self._is_running = False
async def collect_metrics(self) -> SchedulerMetrics:
"""收集当前系统指标"""
# 注意:这是一个简化的实现。在实际系统中,这些指标应从监控模块实时获取。
# 这里我们模拟计算。
avg_latency = 500.0 # 默认值,应从 histogram 计算
throughput = 10.0 # 默认值,应从 counter 计算
queue_length = self.engine.pending_queue.qsize()
units = await self.virt_env.list_units()
unit_resources = {uid: unit.resource_spec for uid, unit in units.items()}
# 更新Prometheus指标(模拟)
workflow_latency_histogram.labels(strategy=self.config['strategy']).observe(avg_latency / 1000.0) # 转换为秒
workflow_throughput_counter.labels(strategy=self.config['strategy']).inc(int(throughput))
for uid, spec in unit_resources.items():
resource_usage_gauge.labels(unit_id=uid, resource_type='cpu').set(spec.cpu_limit)
resource_usage_gauge.labels(unit_id=uid, resource_type='memory_mb').set(spec.memory_limit_mb)
return SchedulerMetrics(avg_latency, throughput, queue_length, unit_resources)
def _make_decision(self, metrics: SchedulerMetrics) -> Dict[str, ResourceSpec]:
"""基于指标和策略做出资源调整决策"""
decisions = {}
strategy = self.config['strategy']
latency_slo = self.config['latency_slo_milliseconds']
adj = self.config['resource_adjustment']
# 简化决策逻辑:
# 1. 如果平均延迟 > SLO,倾向于增加资源(尤其是高CPU消耗的技能)。
# 2. 如果队列过长,增加资源以提升吞吐。
# 3. 根据策略调整激进程度。
scale_factor = 1.0
if strategy == "latency_first":
scale_factor = 1.5 # 更积极地增加资源以降低延迟
elif strategy == "throughput_first":
scale_factor = 0.7 # 更保守,容忍更高延迟以节省资源
for unit_id, current_spec in metrics.unit_resources.items():
new_cpu = current_spec.cpu_limit
new_mem = current_spec.memory_limit_mb
# 决策示例:如果延迟超标,增加CPU
if metrics.avg_latency_ms > latency_slo:
new_cpu = min(current_spec.cpu_limit + adj['cpu_step'] * scale_factor, adj['max_cpu'])
elif metrics.avg_latency_ms < latency_slo * 0.7 and metrics.queue_length < 5:
# 延迟很低且队列空闲,可以适当缩减资源
new_cpu = max(current_spec.cpu_limit - adj['cpu_step'] * 0.5, adj['min_cpu'])
# 内存调整逻辑(示例):根据CPU比例调整
cpu_ratio = new_cpu / current_spec.cpu_limit if current_spec.cpu_limit > 0 else 1.0
new_mem = int(min(max(current_spec.memory_limit_mb * cpu_ratio, adj['min_memory_mb']), adj['max_memory_mb']))
if abs(new_cpu - current_spec.cpu_limit) > 0.05 or abs(new_mem - current_spec.memory_limit_mb) > 10:
decisions[unit_id] = ResourceSpec(cpu_limit=round(new_cpu, 2), memory_limit_mb=new_mem)
return decisions
async def _apply_decisions(self, decisions: Dict[str, ResourceSpec]):
"""应用资源调整决策到对应的执行单元"""
units = await self.virt_env.list_units()
for unit_id, new_spec in decisions.items():
if unit_id in units:
unit = units[unit_id]
success = await unit.update_resources(new_spec)
if success:
print(f"Scheduler: Updated {unit_id} resources to CPU={new_spec.cpu_limit}, Mem={new_spec.memory_limit_mb}MB")
async def run_scheduling_loop(self):
"""调度器主循环"""
self._is_running = True
interval = self.config['update_interval_seconds']
print(f"Dynamic scheduler started with strategy '{self.config['strategy']}', interval {interval}s.")
while self._is_running:
try:
await asyncio.sleep(interval)
metrics = await self.collect_metrics()
self.metrics_history.append(metrics)
# 保留最近100条记录
if len(self.metrics_history) > 100:
self.metrics_history.pop(0)
decisions = self._make_decision(metrics)
if decisions:
await self._apply_decisions(decisions)
except asyncio.CancelledError:
break
except Exception as e:
print(f"Scheduler loop error: {e}")
def stop(self):
self._is_running = False
文件路径: monitor/metrics.py
"""
Prometheus指标定义与暴露。
"""
from prometheus_client import start_http_server, Histogram, Counter, Gauge
import yaml
# 加载配置
with open('config.yaml', 'r') as f:
config = yaml.safe_load(f)
prom_port = config['monitoring']['prometheus_port']
# 定义指标
workflow_latency_histogram = Histogram(
'workflow_latency_seconds',
'Latency of completed workflows in seconds',
['strategy']
)
workflow_throughput_counter = Counter(
'workflow_throughput_total',
'Total number of completed workflows',
['strategy']
)
resource_usage_gauge = Gauge(
'execution_unit_resource',
'Current resource allocation of an execution unit',
['unit_id', 'resource_type'] # resource_type: 'cpu' or 'memory_mb'
)
def start_monitoring_server():
"""启动Prometheus指标HTTP服务器"""
start_http_server(prom_port)
print(f"Monitoring server started on port {prom_port}")
文件路径: main.py
"""
项目主入口,初始化并启动所有组件。
"""
import asyncio
import signal
import yaml
from workflow.engine import WorkflowEngine
from virtualization.docker_env import DockerVirtualizationEnv
from scheduler.dynamic_scheduler import DynamicResourceScheduler
from monitor.metrics import start_monitoring_server
import threading
def load_config():
with open('config.yaml', 'r') as f:
return yaml.safe_load(f)
async def main():
config = load_config()
print("Starting Agent Virtualization Tuning Demo...")
# 1. 启动监控服务器(在独立线程中)
threading.Thread(target=start_monitoring_server, daemon=True).start()
# 2. 初始化虚拟化环境
virt_env = DockerVirtualizationEnv(config['virtualization'])
# 3. 初始化工作流引擎
engine = WorkflowEngine(virt_env, config['workflow']['max_queue_size'])
# 4. 初始化动态调度器
scheduler = DynamicResourceScheduler(virt_env, engine, config)
# 5. 创建后台任务
engine_task = asyncio.create_task(engine.run())
scheduler_task = asyncio.create_task(scheduler.run_scheduling_loop())
# 6. 优雅停机处理
loop = asyncio.get_running_loop()
stop_event = asyncio.Event()
for sig in (signal.SIGINT, signal.SIGTERM):
loop.add_signal_handler(sig, stop_event.set)
print("System is running. Press Ctrl+C to stop.")
print(f" - Workflow Engine: Active")
print(f" - Dynamic Scheduler: Active (strategy: {config['scheduler']['strategy']})")
print(f" - Metrics: http://localhost:{config['monitoring']['prometheus_port']}/metrics")
print("\nYou can now run `python run_workload.py` to generate workload.")
await stop_event.wait()
print("\nShutting down...")
# 7. 清理
scheduler.stop()
scheduler_task.cancel()
engine_task.cancel()
await asyncio.gather(scheduler_task, engine_task, return_exceptions=True)
# 停止所有执行单元
units = await virt_env.list_units()
stop_tasks = [unit.stop() for unit in units.values()]
await asyncio.gather(*stop_tasks, return_exceptions=True)
print("Shutdown complete.")
if __name__ == "__main__":
asyncio.run(main())
文件路径: run_workload.py
"""
生成模拟工作流负载的脚本。
"""
import asyncio
import random
import sys
import uuid
from main import load_config, WorkflowEngine, DockerVirtualizationEnv
async def submit_random_workflow(engine: WorkflowEngine):
"""提交一个随机步骤的工作流"""
steps = []
skills = ["text_processor", "ai_inference", "data_aggregator"]
num_steps = random.randint(2, 4)
for i in range(num_steps):
skill = random.choice(skills)
input_data = f"Payload-{uuid.uuid4().hex[:6]} for step {i+1}"
steps.append({"skill": skill, "input": input_data})
try:
wf_id = await engine.submit_workflow(steps)
print(f" Submitted workflow {wf_id} with {num_steps} steps.")
return True
except Exception as e:
print(f" Failed to submit workflow: {e}")
return False
async def continuous_workload(duration_seconds: int = 60, request_per_second: float = 2.0):
"""持续生成负载"""
config = load_config()
virt_env = DockerVirtualizationEnv(config['virtualization'])
engine = WorkflowEngine(virt_env, config['workflow']['max_queue_size'])
# 启动引擎处理循环(独立任务)
engine_task = asyncio.create_task(engine.run())
interval = 1.0 / request_per_second
end_time = asyncio.get_event_loop().time() + duration_seconds
print(f"Starting workload for {duration_seconds} seconds at {request_per_second} req/s...")
count = 0
while asyncio.get_event_loop().time() < end_time:
start = asyncio.get_event_loop().time()
success = await submit_random_workflow(engine)
if success:
count += 1
elapsed = asyncio.get_event_loop().time() - start
await asyncio.sleep(max(0, interval - elapsed))
print(f"Workload finished. Submitted {count} workflows.")
engine_task.cancel()
try:
await engine_task
except asyncio.CancelledError:
pass
# 简单清理
units = await virt_env.list_units()
for unit in units.values():
await unit.stop()
if __name__ == "__main__":
if len(sys.argv) > 1:
duration = int(sys.argv[1])
else:
duration = 60
if len(sys.argv) > 2:
rps = float(sys.argv[2])
else:
rps = 2.0
asyncio.run(continuous_workload(duration, rps))
文件路径: tests/test_workflow.py
"""
工作流引擎单元测试。
"""
import pytest
import asyncio
from unittest.mock import AsyncMock, MagicMock
from workflow.engine import WorkflowEngine, WorkflowStep
from virtualization.base import VirtualizationEnv, ExecutionUnit, ResourceSpec
@pytest.mark.asyncio
async def test_workflow_submission():
"""测试工作流提交"""
mock_env = MagicMock(spec=VirtualizationEnv)
mock_env.create_unit = AsyncMock()
mock_unit = MagicMock(spec=ExecutionUnit)
mock_unit.unit_id = "test-unit"
mock_unit.resource_spec = ResourceSpec(1.0, 512)
mock_unit.status = "running"
mock_unit.start = AsyncMock()
mock_unit.execute = AsyncMock(return_value={"success": True, "output": "test output", "execution_time_ms": 50})
mock_env.create_unit.return_value = mock_unit
engine = WorkflowEngine(mock_env, max_queue_size=10)
steps_def = [{"skill": "text_processor", "input": "Hello"}]
wf_id = await engine.submit_workflow(steps_def)
assert wf_id.startswith("wf-")
assert engine.pending_queue.qsize() == 1
# 注意:由于引擎处理是异步的,这里可能需要等待或直接测试提交逻辑
@pytest.mark.asyncio
async def test_skill_execution():
"""测试技能执行"""
from workflow.skills import SKILL_REGISTRY
# 确保技能存在
assert "text_processor" in SKILL_REGISTRY
skill = SKILL_REGISTRY["text_processor"]
assert skill.name == "text_processor"
assert "python -c" in skill.command
4. 安装依赖与运行步骤
4.1 前置条件
- 系统: Linux, macOS 或 WSL2 (Windows Subsystem for Linux 2)。
- Docker: 确保Docker守护进程已安装并正在运行。运行
docker --version确认。 - Python: Python 3.9 或更高版本。
4.2 安装步骤
- 克隆/创建项目目录:
mkdir agent-virt-tuning && cd agent-virt-tuning
- 将上述所有代码文件按照"项目结构树"放置到对应目录。
- 安装Python依赖:
pip install -r requirements.txt
4.3 运行系统
- 启动主系统 (在一个终端中):
python main.py
系统将启动,并显示监控地址。此时工作流引擎和调度器已就绪,但还没有负载。
- 生成模拟负载 (在另一个终端中):
# 默认运行60秒,每秒2个请求
python run_workload.py
# 自定义运行120秒,每秒5个请求
# python run_workload.py 120 5
观察第一个终端中的日志,你会看到工作流被提交、执行,以及调度器动态调整资源的记录。
- 查看监控指标:
打开浏览器,访问http://localhost:8000/metrics,你将看到Prometheus格式的指标数据。
4.4 (可选) 使用Grafana可视化
- 安装并运行Grafana (参考官方文档)。
- 将Prometheus (
http://localhost:8000) 添加为数据源。 - 导入仪表板,使用类似以下的PromQL查询创建图表:
- 平均延迟:
rate(workflow_latency_seconds_sum{strategy="balanced"}[5m]) / rate(workflow_latency_seconds_count{strategy="balanced"}[5m]) - 吞吐率:
rate(workflow_throughput_total{strategy="balanced"}[5m]) - CPU分配:
execution_unit_resource{resource_type="cpu"}
- 平均延迟:
5. 测试与验证步骤
5.1 运行单元测试
pytest tests/ -v
这将运行 test_workflow.py 中的测试用例,验证工作流提交和技能注册的基本功能。
5.2 手动接口验证
系统运行后,你可以编写一个简单的脚本进行快速验证:
# quick_test.py
import asyncio
import sys
sys.path.insert(0, '.')
from main import load_config, WorkflowEngine, DockerVirtualizationEnv
async def test():
config = load_config()
virt_env = DockerVirtualizationEnv(config['virtualization'])
engine = WorkflowEngine(virt_env, 10)
# 启动引擎
engine_task = asyncio.create_task(engine.run())
# 提交一个简单工作流
steps = [{"skill": "text_processor", "input": "Quick Test Input"}]
wf_id = await engine.submit_workflow(steps)
print(f"Submitted: {wf_id}")
# 等待几秒让任务处理
await asyncio.sleep(3)
# 检查实例状态(简化,实际应从引擎获取)
print("Test completed. Check main console for execution logs.")
engine_task.cancel()
await engine_task
if __name__ == "__main__":
asyncio.run(test())
运行: python quick_test.py
6. 性能调优实践与扩展
6.1 调优策略实验
修改 config.yaml 中的 scheduler.strategy 为 latency_first 或 throughput_first,重新运行系统并施加负载。观察不同策略下:
- 工作流的完成延迟 (
workflow_latency_seconds) - 系统整体吞吐 (
workflow_throughput_total) - 执行单元的平均资源使用率 (
execution_unit_resource)
你将看到latency_first策略倾向于分配更多资源,延迟较低但资源利用率可能下降;throughput_first策略则相反。
6.2 核心权衡关系可视化
图1:延迟与吞吐的核心权衡关系。动态调度器的目标是在延迟SLO(红色虚线框)的约束下,寻找整体吞吐与资源利用率的最优平衡点。
6.3 智能体工作流执行序列图
图2:智能体工作流执行与动态资源调度序列。展示了从工作流提交到步骤在独立容器单元中执行,以及后台调度器周期性收集指标并调整资源限额的完整流程。
6.4 扩展方向
- 更真实的技能:将技能命令替换为调用真实的机器学习模型API(如加载TensorFlow模型)、数据库查询或外部工具。
- 高级调度算法:实现基于强化学习(RL)的调度器,根据历史指标预测未来负载并提前调整资源。
- 多级虚拟化:支持
gVisor或Kata Containers作为执行环境,比较其安全开销对性能的影响。 - Kubernetes集成:将
ExecutionUnit实现为Kubernetes Pod,利用K8s的Horizontal Pod Autoscaler (HPA) 和 Vertical Pod Autoscaler (VPA) 进行伸缩,与本项目的调度器进行对比。 - 混沌工程测试:在系统中注入网络延迟、模拟容器故障,测试调度器的容错与恢复能力。
通过本项目,你不仅获得了一个可运行的研究原型,更得到了一个可以深入探索虚拟化智能体系统性能调优的实验平台。核心在于理解监控数据、做出决策并验证效果这一闭环,这是云原生智能体系统运维的关键能力。