【以下的问题经过翻译处理】 这是我在stackoverflow上问过的一个问题的副本。
我正在使用[AWS提供的指南]https://sagemaker-examples.readthedocs.io/en/latest/advanced_functionality/scikit_bring_your_own/scikit_bring_your_own.html#When-should-I-build-my-own-algorithm-container%3F通过自定义docker容器提供Sagemaker模型。这个docker容器运行一个简单的nginx->gunicorn/wsgi->flask服务器。
我的问题是,无论在哪个实例中,转换请求都会在约30分钟时超时,尽管应该能够一直持续到60分钟。由于请求数据密集,我需要使请求能够达到最大60分钟。通过几个月的调试经验,我知道有3个因素应影响服务器响应请求所需的时间:
- Sagemaker根据创建批处理转换作业时设置的“InvocationsTimeoutInSeconds”参数https://docs.aws.amazon.com/sagemaker/latest/APIReference/API_ModelClientConfig.html#sagemaker-Type-ModelClientConfig-InvocationsTimeoutInSeconds
- nginx.conf配置文件里keepalive_timeout、proxy_read_timeout、proxy_send_timeout和proxy_connect_timeout都等于或大于最大超时。
- Gunicorn服务器必须配置为超时等于或大于最大超时。
我已验证,在创建批处理转换作业时,InvocationsTimeoutInSeconds设置为3600(1小时)。
nginx.conf配置如下:
worker_processes 1;
daemon off; # Prevent forking
pid /tmp/nginx.pid;
error_log /var/log/nginx/error.log;
events {
defaults
}
http {
include /etc/nginx/mime.types;
default_type application/octet-stream;
access_log /var/log/nginx/access.log combined;
sendfile on;
client_max_body_size 30M;
keepalive_timeout 3920s;
upstream gunicorn {
server unix:/tmp/gunicorn.sock;
}
server {
listen 8080 deferred;
client_max_body_size 80m;
keepalive_timeout 3920s;
proxy_read_timeout 3920s;
proxy_send_timeout 3920s;
proxy_connect_timeout 3920s;
send_timeout 3920s;
location ~ ^/(ping|invocations) {
proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
proxy_set_header Host $http_host;
proxy_redirect off;
proxy_pass http://gunicorn;
}
启动gunicorn服务如下:
def start_server():
print('Starting the inference server with {} workers.'.format(model_server_workers))
print('Model server timeout {}.'.format(model_server_timeout))
# link the log streams to stdout/err so they will be logged to the container logs
subprocess.check_call(['ln', '-sf', '/dev/stdout', '/var/log/nginx/access.log'])
subprocess.check_call(['ln', '-sf', '/dev/stderr', '/var/log/nginx/error.log'])
nginx = subprocess.Popen(['nginx', '-c', '/opt/program/nginx.conf'])
gunicorn = subprocess.Popen(['gunicorn',
'--timeout', str(3600),
'-k', 'sync',
'-b', 'unix:/tmp/gunicorn.sock',
'--log-level', 'debug',
'-w', str(1),
'wsgi:app'])
signal.signal(signal.SIGTERM, lambda a, b: sigterm_handler(nginx.pid, gunicorn.pid))
# If either subprocess exits, so do we.
pids = set([nginx.pid, gunicorn.pid])
while True:
pid, _ = os.wait()
if pid in pids:
break
sigterm_handler(nginx.pid, gunicorn.pid)
print('Inference server exiting')
尽管如此,只要转换作业花费的时间超过30分钟,我就会在日志中看下面的内容,并且转换作业状态变为失败:
2023/01/07 08:23:14 [error] 11#11: *4 upstream prematurely closed connection while reading response header from upstream, client: 169.254.255.130, server: , request: "POST /invocations HTTP/1.1", upstream: "http://unix:/tmp/gunicorn.sock:/invocations", host: "169.254.255.131:8080"
我认为AWS批量转换中存在错误,但也许我缺少一些其他变量(可能在nginx.conf 中),这些变量可能会导致我的上游请求过早终止。
location / {
return 404 "{}";
}
}
}`
我像这样启动gunicorn服务器:(代码部分不翻译)尽管如此,每当转换作业持续时间超过约30分钟时,我会在日志中看到该消息,并且转换作业状态将变为失败。我接近认为AWS批处理转换存在缺陷,但也许我错过了其它一些变量(或许是在nginx.conf中)可能会导致请求的上游提前终止。