daemon

python多进程编程中常常能用到的几种方法

由 a 夏天 提交于 2020-01-05 10:54:52
python中的多线程其实并不是真正的多线程，如果想要充分地使用多核CPU资源，在python中大部分情况需要使用多进程。python提供了非常好用的多进程包Multiprocessing，只需要定义一个函数，python会完成其它所有事情。借助这个包，可以轻松完成从单进程到并发执行的转换。multiprocessing支持子进程、通信和共享数据、执行不同形式的同步，提供了Process、Queue、Pipe、LocK等组件 一、Process 语法：Process([group[,target[,name[,args[,kwargs]]]]]) 参数含义：target表示调用对象；args表示调用对象的位置参数元祖；kwargs表示调用对象的字典。name为别名，groups实际上不会调用。 方法：is_alive()： 　　　join(timeout)： 　　　run()： 　　　start()： 　　　terminate()： 属性：authkey、daemon(要通过start()设置)、exitcode(进程在运行时为None、如果为-N，表示被信号N结束)、name、pid。其中daemon是父进程终止后自动终止，且自己不能产生新的进程，必须在start()之前设置。 1.创建函数，并将其作为单个进程 ''' 遇到问题没人解答？小编创建了一个Python学习交流QQ群

Proper way to start thread from python daemon

由 南楼画角 提交于 2020-01-05 08:37:15
问题 I need to write simple daemon with web interface. The idea is to use python-daemon package and run wsgiref.simple_server inside one thread. Daemon works fine with the following code : import daemon import logging import time import signal import threading logfilename = '/var/log/testdaemon.log' logger = logging.getLogger("DaemonLog") logger.setLevel(logging.INFO) formatter = logging.Formatter( '%(asctime)s:%(levelname)s:%(message)s', '%Y-%m-%d %H:%M:%S') handler = logging.FileHandler

nvm: reference “default” node version path in Shell script

由 跟風遠走 提交于 2020-01-05 02:30:46
问题 I'm writing a daemon script for Linux Debian, and I'd need to be able to access the $NVM_BIN shell environment variable, or somehow reference the path to the current "default" Node version as set in nvm. Several of these daemon scripts will be running on the system. Since all these scripts can share the same Node version, I'd like to reference some variable that gets automatically updated when I install a new version of Node and define it as "default", without having to manually change the

oracle 12C RAC 集群日志（cluster log)目录

由 青春壹個敷衍的年華 提交于 2020-01-05 00:28:12
[grid@shurkcs ~]$ adrci ADRCI: Release 12.2.0.1.0 - Production on Thu Mar 1 09:25:45 2018 Copyright (c) 1982, 2017, Oracle and/or its affiliates. All rights reserved. ADR base = "/U01/u01/grid" adrci> show homes ADR Homes: diag/asm/user_root/host_3751460993_107 diag/asm/user_grid/host_3751460993_107 diag/asm/+asm/+ASM diag/crs/shurkcs/crs diag/clients/user_root/host_3751460993_107 diag/clients/user_grid/host_3751460993_107 diag/clients/user_oracle/host_3751460993_107 diag/tnslsnr/shurkcs/listener diag/asmtool/user_root/host_3751460993_107 diag/asmtool/user_grid/host_3751460993_107 diag/afdboot

How to intall Tomcat as a daemon on OS X?

由 守給你的承諾、 提交于 2020-01-04 06:23:47
问题 How do I install Tomcat as a daemon on OS X? It should run even when a user is not logged on. I could probably survive installing Tomcat for a single users and having it run at log in, for now. But long term I need it installed and running as a service on boot. 回答1: You could write your own LaunchDaemon script for it. Launch Services can be used to set up user or system-based startup. 回答2: See Updated for 2009 at the bottom of the page for details on what is needed 回答3: What Matthew and

Periodically fetch data and display it with Django

由 落花浮王杯 提交于 2020-01-03 01:55:21
问题 I would like to implement a kind of "real-time" notification system in my Django application. I would store some messages destined to a specific user in my database. When a user is logged in the application, if there is a notification for him in the database, then the application displays it using the messages framework. When he clicks on the message, it is deleted from the database. I am a bit stuck on the "fetch the data every minute" thing. I heard of celery (http://docs.celeryproject.org

Java service on Linux - How to ensure constant uptime. Deamon, Shell script or Wrapper?

由 旧城冷巷雨未停 提交于 2020-01-02 23:03:54
问题 I have a Java worker that are polling a external queue system for jobs, through web service calls. What is the most solid way to ensure that the worker is operating at any given time? 回答1: JVM execution is not different from any other program. So what you want to do is to put together a shell script and place it in /etc/init.d and link it appropriatelly to to /etc/rc.d. On RedHat flavors it will ensure service startup with the system. Wring the script may be tricky, but I would copy one of

Java service on Linux - How to ensure constant uptime. Deamon, Shell script or Wrapper?

由 白昼怎懂夜的黑 提交于 2020-01-02 23:02:57
问题 I have a Java worker that are polling a external queue system for jobs, through web service calls. What is the most solid way to ensure that the worker is operating at any given time? 回答1: JVM execution is not different from any other program. So what you want to do is to put together a shell script and place it in /etc/init.d and link it appropriatelly to to /etc/rc.d. On RedHat flavors it will ensure service startup with the system. Wring the script may be tricky, but I would copy one of

process from pcntl_fork not terminating

由 久未见 提交于 2020-01-02 21:20:53
问题 I am running a web service which involved with daemons by php+apache2. So I tried pcntl_fork function. But there is a question that the child process are not terminating even I used exit(0) in the child process's code which result in a lot of apache2 processes. I'm wondering if there is a way to shutdown those useless apache2 processes? PS: because I'm not very aware of the mechanism of signal, so I tried to make daemon by a single call to a agent script which will exit as soon as the child

docker容器安全

由 让人想犯罪 __ 提交于 2020-01-01 13:29:58
title: docker容器安全 tags: Docker,容器,安全策略 grammar_cjkRuby: true --- Docker容器的安全性 1.安全策略-Cgroup 1.限制Cpu docker run --rm -ti -c 2000 ubuntu bash 2.限制内存 docker run --rm -ti -m 200M ubuntu bash 3.限制快设备io docker run --rm -ti --name container1 ubuntu bash dd if=/dev/zero of=testfile0 bs=8k mount=5000 oflag=direct 修改 Cgroup文件 # 查找容器挂载的文件系统“/dev/mapper”的位置 $ mount|grep ContainerID # 查看容器挂载的文件系统中的文件(Path为上条命令取得的返回结果) # 返回结果“->”标记后会有一个新的路径，我们先称其为DeviceFilePath $ ls -l Path # 查询容器挂载的设备号 $ ls DeviceFilePath -l # 返回结果中“root disk”后面会有一串用“,”隔开的数字，假设是128和256 # 限制容器的写速度 $ sudo echo '128:256 10240000' >/sys/fs
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