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Some key windows 2000 files mode they run in number of exported function calls main contents of each file Calls in win32k.sys not formally exported not called directly

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10.1 History of unix 10.2 Overview of unix 10.3 Processes in unix 10.4 Memory management in unix 10.5 Input/output in unix 10.6 The unix file system 10.7 Security in unix

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The Biba Model Principles to guarantee integrity of data Simple integrity principle process can write only objects at its security level or lower The integrity * property process can read only objects at its security level or higher

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Linda independent processes communicate via abstract tuple space Tuple like a structure in C, record in Pascal Operations: out, in, read, eval

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Most movies stored on DVD or tape copy to disk when needed results in large startup time keep most popular movies on disk Can keep first few min. of all movies on disk start movie from this while remainder is fetched

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With CPUs faster, memory larger disk caches can also be larger increasing number of read requests can come from cache thus, most disk accesses will be writes LFS Strategy structures entire disk as a log have all writes initially buffered in memory periodically write these to the end of the disk log when file opened, locate i-node, then fin...

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Telling the programs to use less energy may mean poorer user experience Examples change from color output to black and white speech recognition reduces vocabulary less resolution or detail in an image

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Virtual memory and I/O occasionally interact Proc issues call for read from device into buffer while waiting for I/O, another processes starts up has a page fault buffer for the first proc may be chosen to be paged out Need to specify some pages locked exempted from being target pages

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Algorithm to allocate a resource may be to give to shortest job first Works great for multiple short jobs in a system May cause long job to be postponed indefinitely even though not blocked Solution: First-come, first-serve policy

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Separate what is allowed to be done with how it is done a process knows which of its children threads are important and need priority Scheduling algorithm parameterized mechanism in the kernel Parameters filled in by user processes policy set by user process

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