October 2002
Intermediate to advanced
1154 pages
49h 36m
English
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Chapter 26. System Performance and Profiling
Timing Is Everything
Whether you are a system administrator or user, the responsiveness of your Unix system is going to be the primary criterion of evaluating your machine. Of course, “responsiveness” is a loaded word. What about your system is responsive? Responsive to whom? How fast does the system need to be to be responsive? There is no one silver bullet that will slay all system latencies, but there are tools that isolate performance bottlenecks — the most important of which you carry on your shoulders.
This chapter deals with issues that affect system performance generally and how you go about finding and attenuating system bottlenecks. Of course, this chapter cannot be a comprehensive guide to how to maximize your system for your needs, since that is far too dependent on the flavors of Unix and the machines on which they run. However, there are principles and programs that are widely available that will help you assess how much more performance you can expect from your hardware.
One of the fundamental illusions in a multiuser, multiprocessing operating system like Unix is that every user and every process is made to think that they are alone on the machine. This is by design. At the kernel level, a program called the scheduler attempts to juggle the needs of each user, providing overall decent performance of:
Keeping interactive sessions responsive
Processing batch jobs promptly
Maximizing CPU utilization[1]
Cranking through as many ...
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O’Reilly covers everything we've got, with content to help us build a world-class technology community, upgrade the capabilities and competencies of our teams, and improve overall team performance as well as their engagement.Julian F.
I wanted to learn C and C++, but it didn't click for me until I picked up an O'Reilly book. When I went on the O’Reilly platform, I was astonished to find all the books there, plus live events and sandboxes so you could play around with the technology.Addison B.
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I'm always learning. So when I got on to O'Reilly, I was like a kid in a candy store. There are playlists. There are answers. There's on-demand training. It's worth its weight in gold, in terms of what it allows me to do.