scheduling

问题 I have to write a CPU scheduling simulation with kernel level threads. I have to be able to use either first come first served (FCFS) or round robin (RR) algorithms. Data for the processes and their threads is given in the form of a text file. At the moment my program reads in the text file data into linked lists. I'm not really sure how to start the simulation (I've never programmed a simulation before). Is this how I would proceed in the case of FCFS? When I get to the first thread of the

问题 So I'm in a bit of a difficult algorithm modeling situation and I hope you guys can help me find some directions. The problem came of logistics department of my company, and as a CS intern, I wasn't able to find a solution yet The problem: Given a fixed amount of time, a fixed number of workers and a set of feaseble tasks, assign tasks to workers in such a way that all workers be as busy as possible, and the last worker of the group is only assigned to the remaining tasks that others weren't

问题 I am trying to create a state diagram of a submitted spark application. I and kind of lost on when then an application is considered FAILED. States are from here: https://github.com/apache/spark/blob/d6dc12ef0146ae409834c78737c116050961f350/core/src/main/scala/org/apache/spark/deploy/master/DriverState.scala 回答1: This stage is very important, since when it comes to Big Data , Spark is awesome, but let's face it, we haven't solve the problem yet! When a task/job fails, Spark restarts it

问题 Is it possible calling a service (web service or wcf service) via a ssis package in order to schedule running it as a job? Thank you for any sugestions 回答1: Yes, you can invoke a web service from an SSIS package. http://msdn.microsoft.com/en-us/library/ms140114.aspx http://www.codeproject.com/KB/database/webservicessis.aspx Whether or not that's a good design decision is another question: Does it couple the tiers too tightly? Is it secure? (probably, if you are only making outgoing calls, or

问题 In a multi-threaded Java application, if I want to identify the instructions where the context switch from one thread to another happens, what is the best approach? Instrumenting every instruction to identify what thread is executing the instruction will give a close approximation. For example, if the switch happens after the instrumentation is executed and before the actual instr. is executed, then the result will be imprecise. Is there a way to precisely identify the context switch location

问题 I have read that Java threads are user-level threads and one of the differences between user level threads and kernel level threads is that kernel level threads are scheduled by the kernel(we cannot change it) where as for user level threads we can define our own scheduling algorithm. So how do we schedule threads in Java? At any given time, when multiple threads are ready to be executed, the runtime system chooses the Runnable thread with the highest priority for execution. If two threads of

问题 I am writing a Hadoop scheduler. My scheduling requires finding the CPU time taken by each Map/Reduce task. I know that: The TaskInProgress class maintains the execStartTime and execFinishTime values which are wall-clock times when the process started and finished, but they do not accurately indicate the CPU time consumed by the task. Each task is executed in a new JVM, and I could use the OperatingSystemMXBean.getProcessCpuTime () method, but again the description of the method tells me:

问题 I want to make an SMS scheduling app, that sends SMS at predefined time. I have decided to use a timer for that purpose. During my research, I found out that Alarm Manager was more appropriate option for scheduling one time events in android. Any guidance would be fruitful. I want to implement the timer in my service as shown in the give code: public class SMSTimerService extends Service { private Timer timer = new Timer(); Long delay = 10000L;//for long we have to keep L at the last of the

问题 I need a functionality in storm that i know (based on the docs) has not been yet implemented. I need to add more tasks at runtime without the need to have an initial large number of tasks, because it might cause performance issues. because Running more than one task per executor does not increase the level of parallelism -- an executor always has one thread that it uses for all of its tasks, which means that tasks run serially on an executor. I know that rebalance command can be used to add

问题 I am using Spring 4.0.2 for my Web Application. My Web Application is about file processing. There are some statues about files like "In Progress", "On Hold", "Completed" . One user can complete multiple files, but only one at a time. So at a time only one file must be "In Progress" for a single user. Now, I want to check after every 15 mins whether is there any event occurred with particular file or not. If there is no event occurred, I want to change file status from "In Progress" to "On