Multiprocessor thread scheduling strategies

Load Sharing: Processes are not assigned to a particular processor. A global queue of threads is maintained. Each processor, when idle, selects a thread from this queue. Note that load balancing refers to a scheme where work is allocated to processors on a more permanent basis.

Gang Scheduling: A set of related threads is scheduled to run on a set of processors at the same time, on a 1-to-1 basis. Closely related threads / processes may be scheduled this way to reduce synchronization blocking, and minimize process switching. Group scheduling predated this strategy.

Dedicated processor assignment: Provides implicit scheduling defined by assignment of threads to processors. For the duration of program execution, each program is allocated a set of processors equal in number to the number of threads in the program. Processors are chosen from the available pool.

Dynamic scheduling: The number of thread in a program can be altered during the course of execution.

Short,Medium and Long term scheduler

Long term scheduler determines which programs are admitted to the system for processing. It controls the degree of multiprogramming. Once admitted, a job becomes a process.

For more details , please visit here and here.

Medium term scheduling is part of the swapping function. This relates to processes that are in a blocked or suspended state. They are swapped out of real-memory until they are ready to execute. The swapping-in decision is based on memory-management criteria.

Short term scheduler, also know as a dispatcher executes most frequently, and makes the finest-grained decision of which process should execute next. This scheduler is invoked whenever an event occurs. It may lead to interruption of one process by preemption.

For more details , please visit here and here.

OS-9

I was trying to write this post from last 2 years, but always i postponed it.Now I have decided to done it.This post is about an operating system OS-9 from legacy systems developed by Microware.OS-9 is a real-time, multiuser, multitasking operating system developed by Microware Systems Corporation. It provides synchronization and mutual exclusion primitives in the form of signals, events, and semaphores. It also allows communication between processes in the form of named and unnamed pipes, as well as shared memory in the form of data modules.

OS-9 is modular, allowing new devices to be added to the system simply by writing new device drivers, or if a similar device already exists, by simply creating a new device descriptor. All I/O devices can be treated as files, which unifies the I/O system. In addition, the kernel and all user programs are ROMable. Thus, OS-9 can run on any supported hardware platform from simple diskless embedded control systems to large multiuser minicomputers.

Originally developed for the 6809 microprocessor, OS-9 was a joint effort between Microware and Motorola. The original version of OS-9 (OS-9 Level I) was capable of addressing 64 kilobytes of memory. OS-9 Level II took advantage of dynamic address translation hardware, and allowed a mapped address space of one megabyte on most systems, and up to two megabytes on others, most notably the Tandy Color Computer 3.

In the 1980's, Microware ported OS-9 to the 68000 family of microprocessors, creating OS-9/68000, which is used in a variety of industrial and commercial arenas, including Philips' CD-i and most recently, set-top boxes for interactive television.

Error in Loading Operating System

The Error Loading Operating System error appears when your operating system fails to load properly. This error is localized to the Microsoft Windows XP operating system, so users of other operating systems should not face this problem. Essentially, the Error Loading Operating System occurs at a point between the computer’s BIOS running checks on the system’s hardware and the actual launching of the operating system. This error is usually accompanied by a black screen and occurs directly after the installation of Windows XP.

What causes this error?
You can expect to see the Error Loading Operating System error when there is an issue with the way the BIOS and the Windows XP operating system are communicating with each other. Most commonly, the BIOS has an issue where it does not support or has no way to correctly manage the capacity of the hard drive that Windows XP was installed to.

How can I resolve this error?
The Error Loading Operating System problem can be solved in a variety of different ways. However, it is important that you have some knowledge of computers before you proceed with any of the suggested solutions to this error message. Not knowing exactly what you are doing, or failing to follow the directions you see on your screen could result in the corruption or destruction of your computer. Changing or flashing your BIOS can have detrimental effects on your computer and should only be performed if you are completely sure you know what you are getting into.

Your first step to resolve the Error Loading Operating System issue should be to update your computer’s BIOS. Check your computer’s manual for information on how to do this or call the company which constructed your computer. Alternatively, if you built your computer yourself, consult the manual which came with your motherboard.

Once you are sure that your BIOS has been upgraded to its most recent version, determine which type of BIOS you are using. Each BIOS is somewhat different, and newer versions of popular BIOSes tend to change the locations of different functions and features, so consult your computer vendor, your motherboard manual, or a tech support forum for the most up to date information on how to make sure that your hard drives are interfacing properly with your BIOS.

My true companion Ticket America

If you are an american then you are definitely aware of what exactly ticket america is because it is the only site that made a tremendous growth in last few years in providing best services to its users in the field of entertainment. If you want to know what latest is happening in your town then you can simply visit their site and get to know about all the facilities that they provide in the form of concerts,city guides,sports or any other useful information that you need for your entertainment. In this post I am mainly going to concentrate on all the stadiums where you can get the tickets from here.The biggest point for Ticketamerica is that they are far from unique in applying these extra costs, and it is symptomatic of the ticketing industry in general, rather than this one individual supplier. With ticket america can get a chance to visit all the best stadiums across whole america which includes Bank of America Stadium,Lucas Oil Stadium,Lambeau Field,FedEx Field,Invesco Field and may more in the same list.

Assuming there are tickets remaining to your show, the tickets you have selected will be presented to you. Once they are in your 'basket', you have a limited amount of time to complete the transaction before the tickets are released for other people to buy. This is normally a few minutes worth, but it's often best to have all of your card details at hand to avoid any wasted time. Another alternative is to create an account on the site, whereby all of your personal information is stored, thus making the checkout process a lot quicker.

Review on Ticket America 4

If you are a real fun loving person and fond of visiting different different stadiums and even not getting chance to look on all these then here is a place for you where you can complete any of your game dream. Now here is a great news for american people because with Ticket america you can get a chance see matches in all those stadiums and enjoy matches their. But sometimes it is very difficult to get these tickets because a lot of people want to see the same matches in all those lovely stadiums like Bank of America Stadium,Lucas Oil Stadium,Lambeau Field,FedEx Field,Invesco Field and many more in the same list.

Here I am going to give you some more detail about Yankee Stadium,in Yankee stadium their are two sections at Yankee Stadium that offer fans with a more economical way to see a game, The Tier Reserved outfield and the Bleachers. The Tier Reserved outfield consists of sections 26-36 and 25-35. These sections are nosebleed seats and they are far down the line, but they get you into the park at a cheap price. The Bleacher sections are better in that they are not elevated as high but as with many bleacher sections in most MLB parks a birds eye view is hard to come by. Bleacher sections are numbered as 37 to 59. If your fortunate enough to sit in the lower rows of the Bleachers, you will be able to get a nice view of the bullpens. Again, these two sections get you in and allow you to indulge in few extra brews.

Review on Ticket America 3

If you plan to attend any kind of ticketed event on your travels to the USA, then I can give a big thumbs up to Ticketmaster.com, the biggest provider around, and in my experience, also the best. I've used this service several times when attending sporting events in the USA, and it works quite smoothly, so I have no real complaints at all about the service. The biggest negative for Ticketmaster is their hefty service and transaction charges that are applied to each order, but they are far from unique in applying these extra costs, and it is symptomatic of the ticketing industry in general, rather than this one individual supplier. You can book the tickets for any of your favorite matches,it may be kentucky basket ball match tickets,george town hoyas basket ball group, tennessee vols mens basketball group or kansas state wildcats mens basketball match.

Assuming there are tickets remaining to your show, the tickets you have selected will be presented to you. Once they are in your 'basket', you have a limited amount of time to complete the transaction before the tickets are released for other people to buy. This is normally a few minutes worth, but it's often best to have all of your card details at hand to avoid any wasted time. Another alternative is to create an account on the site, whereby all of your personal information is stored, thus making the checkout process a lot quicker.