In a preemptive priority based RTOS, priority inversion problem is among the major sources of deadline violations. Priority inheritance protocol is one of the approaches to reduce priority inversion. Unfortunately, RTOS like uC/OS can’t support priority inheritance protocol since it does not allow kernel to have multiple tasks at the same priority. Although it has different ways to avoid priority inversion such as priority ceiling protocol, developers still have some difficulties in programming real time applications with it. In this paper, we redesign the uC/OS kernel to provide the ability to support round robin scheduling and implement priority inheritance semaphore on the modified kernel. As result, we port new kernel with priority inheritance semaphore to evaluation board, and evaluate the execution time of each of the kernel service as well as verify the operations of our implementation.
标签： priority preemptive inversion problem
上传时间： 2015-12-14
上传用户：气温达上千万的
The main purpose of this project is to add a new scheduling algorithm to GeekOS and to implement a simple synchronization primitive (semaphore). As you might have already noticed, GeekOS uses a simple priority based preemptive Round robin algorithm. In this project, you will change this to a multilevel feedback scheduling. In addition, you will provide user programs with semaphores, a means to check the system s current time and a mechanism for passing command-line arguments
标签： scheduling algorithm implement to
上传时间： 2013-11-27
上传用户：Late_Li
1、在Tomcat的Webapps目录下建立一个目录，例如oa。 2、将程序代码的build/web/目录下的全部文件复制到Tomcat的webapps目录下oa目录。 3、启动Tomcat 4、在地址栏中输入http://localhost:8080/oa 缺省用户： robin 管理员， 密码：111111 RL 用户， 密码：222222 用户可以自己注册用户或者修改data目录下的users.xml文件。
上传时间： 2013-12-22
上传用户：小宝爱考拉
本系统为在线相册系统，使用方法（这里假定Tomcat安装在本机，且为缺省的配置）： 1、在Tomcat的Webapps目录下建立一个目录，例如oa。 2、将程序代码的build/web/目录下的全部文件复制到Tomcat的webapps目录下oa目录。 3、启动Tomcat 4、在地址栏中输入http://localhost:8080/oa 缺省用户： robin 管理员， 密码：111111 RL 用户， 密码：222222 用户可以自己注册用户或者修改data目录下的users.xml文件。
标签：
上传时间： 2013-12-20
上传用户：561596
