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-rw-r--r--report/2in25-report.pdfbin159432 -> 162354 bytes
-rw-r--r--report/chapter1.tex8
-rw-r--r--report/chapter5.tex4
-rw-r--r--report/chapter6.tex36
4 files changed, 7 insertions, 41 deletions
diff --git a/report/2in25-report.pdf b/report/2in25-report.pdf
index 93ea2b4..05ed5c9 100644
--- a/report/2in25-report.pdf
+++ b/report/2in25-report.pdf
Binary files differ
diff --git a/report/chapter1.tex b/report/chapter1.tex
index 3fa54b5..9102563 100644
--- a/report/chapter1.tex
+++ b/report/chapter1.tex
@@ -1,13 +1,13 @@
\section{Introduction}
-Our world is getting more and more surrounded by electronical devices. Only a few years ago our surroundings were limited to Radio's and Televisions. Soon after we got our Microwaves and washing machines, not to mention the boom in the mobile phone corner. All these devices require Operating systems and nearly all require real-time operating systems. \\
+Our world is getting more and more surrounded by electronic devices. Only a few years ago our surroundings were limited to radio's and televisions. Soon after we got our microwaves and washing machines, not to mention the boom in the mobile phone corner. All these devices require operating systems and nearly all of these OS require real-time computations. \\
To define a real-time operating system is beyond the scope of this article, what is not however is that all (real-time) operating systems use some sort of scheduling algorithm. \\
-We have done a literature study concerining one of these algorithms, called Fixed Priority Deferred Schedule (FPDS) and looked at various aspects of it. \\
+We have done a literature study concerning one of these algorithms, called Fixed Priority Scheduling with Deferred Preemtion (FPDS) and looked at various aspects of it. In chapter 2 we discuss development considerations while the architectural considerations are dealt with in chapter 3. The next chapter, chapter 4, is all about the application domains of FPDS. We conclude our report with some small results and notes on the discussion held after our presentation on this subject.
\section{Motivation}
-FPPS does many great things. One of which however is not, dealing with caches. Caches are great things if you can use them. Audio/Video almost always work a lot faster with caches, so if you like to use caches in a real-time system, there is a scheduling algorythm that allows exactly this, namly is FPDS. FPDS allows the uses of caches, and still behaves like a real-time system. \\
+Fixed priority scheduling with preemption (FPPS) is already widely used. In the case of FPPS with the use of cash brings great unpredictability. Caches are great for performance improvements, if you can use them. Audio/Video almost always work a lot faster with caches. So if you like to use caches in a real-time system, there is a scheduling algorithm that allows exactly this, namely is FPDS. FPDS allows the uses of caches, and still behaves like a real-time system. \\
-Resource control can get complex very fast, due to things like Interupt Service Routines (ISR) and buffers to actually access certain resources. With FPPS this is very complex task and introduces a lot of overhead. One of the design goals of FPDS was to simply this and thus also reducing the overhead. \\
+Resource control can get complex very fast, due to things like Interrupt Service Routines (ISR) and buffers to actually access certain resources. With FPPS this is very complex task and introduces a lot of overhead. One of the design goals of FPDS was to simply this and thus also reducing the overhead.
diff --git a/report/chapter5.tex b/report/chapter5.tex
index 15e5700..53a7e9e 100644
--- a/report/chapter5.tex
+++ b/report/chapter5.tex
@@ -1,5 +1,5 @@
\section{Discussion and conclusion}
-If an application requires caches, like Video decoding does, then FPDS is a very interesting option. This because FPDS allows the use of caches, yet allowing the system to act in a real-time manner. This however only, and only if, very occasional misses deadlines are acceptable of high priority tasks, since FPDS allows a lower priority task to block a high priority task. \\
+If an application requires caches, like Video decoding does, then FPDS is a very interesting option. This is because FPDS allows the use of caches, yet allowing the system to act in a real-time manner. This however only, and only if, very occasional misses deadlines are acceptable of high priority tasks, since FPDS allows a lower priority task to block a high priority task. \\
-What however, if there are a lot of cache misses? If this is the case, then you could argue that either, the system was designed wrong, either by using a cache that shouldn't have been used in the first place. Or the cache would not be sufficient. On the other hand, it can be argued that there are several algorithms that prove a system is always scheduable. What these algorithms do not account for when the input data is variable. Like for example a Video-data stream from a satelite. This video data stream is unpredictable and can be out of specification. If this is the case, it may still happen that the scheduler misses it's deadline if the video decoding all of a sudden requires more CPU power. \\
+What however, if there are a lot of cache misses? If this is the case, then you could argue that either, the system was designed wrong, either by using a cache that shouldn't have been used in the first place. Or the cache would not be sufficient. On the other hand, it can be argued that there are several algorithms that prove a system is always schedulable. What these algorithms do not account for when the input data is variable. Like for example a Video-data stream from a satellite. This video data stream is unpredictable and can be out of specification. If this is the case, it may still happen that the scheduler misses it's deadline if the video decoding all of a sudden requires more CPU power.
diff --git a/report/chapter6.tex b/report/chapter6.tex
index 5921ea0..ac0cc4c 100644
--- a/report/chapter6.tex
+++ b/report/chapter6.tex
@@ -1,36 +1,2 @@
-%\section{Literature}
-
-%\small
-%
-%\begin{tabbing}
-%
-%\textbf{[1]} \= Jonathan Simonson, Janak H. Patel. Use of preferred preemption points in cache-based \\
-%\> real-time systems. IEEE Computer Society Washington, DC, USA 1995 \\
-%
-%\\
-%
-%\textbf{[2]} \= Healy, C.A., Whalley, D.B., Harmon, M.G. Integrating the Timing Analysis of Pipelining \\
-%\> and Instruction Caching. Dept. of Comput. Sci., Florida State Univ., Tallahassee, FL 1995 \\
-%
-%\\
-%
-%\textbf{[3]} \= Giorgio C. Buttazzo. Hard Real-Time Computing Systems, 2nd Revised edition \\
-%
-%\\
-%
-%\textbf{[4]} \= Sheayun Lee, Chang-Gun Lee, Minsuk Lee, Sang Lyul Min, Chong Sang Kim. Limited \\
-%\> preemptible scheduling to embrace cache memory in real-time systems. Dept. of Computer \\
-%\> Engineering, Seoul National University and Hansung University Seoul, Korea 1998 \\
-%
-%\\
-%
-%\textbf{[5]} \= Jonathan Simonson, Janak H. Patel. Use of preferred preemption points in cache-based \\
-%\> real-time systems. IEEE Computer Society Washington, DC, USA 1995 \\
-%
-%\\
-%
-%
-%\end{tabbing}
-
\bibliographystyle{alpha}
-\bibliography{references} \ No newline at end of file
+\bibliography{references}