Contents:
Which Time Is It? 
Timing Programs 
The csh time variable 
Average Command Runtimes with runtime 
Why Is the System So Slow? 
lastcomm: What Commands Are Running and How Long Do They Take?
Checking System Load: uptime 
A Big Environment Can Slow You Down 
Know When to Be "nice" to OTher Users...and When
Not to
A nice Gotcha 
Changing a Job's Priority Under BSD UNIX 
What Makes Your Computer Slow? How Do You Fix It?
When we talk about "time" on UNIX systems, we could be talking about two things:
What time it is, as shown by the date (51.10) command, and recorded in countless ways - as file creation and modification times, as the time of last login, and so on.
How long things take.
This chapter is concerned with the latter. It talks about how long programs take to run, what makes them faster or slower, and what you can (or more often can't) do about it.
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