Computer users expect their systems to work well at all times, but unfortunately this isn’t always the case. If your system becomes slow, there certainly is something you can do about it. This article will help you understand what’s happening on the system, whether it’s the computer in front of you or a system you’re accessing remotely.
When we say the system is slow we mean that it isn’t responding to our input in a reasonable time, or taking too long to complete a task. This can happen when there is *another* program using too many system resources, starving *your* program of resources, causing it to run slowly
There are three common ways in which this can happen, and all three of these scenarios can be equally crippling and put your system into a state where it seems to be frozen.
A program is monopolizing the cpu.
A program is using all of the cpu cycles, blocking access to the cpu to other programs. This may be intentional (programs that do heavy processing) or accidental (programs get stuck repeating something over and over).
You’re nearly out of physical memory.
You are either running too many programs, or programs that use too much memory. Your physical memory is almost entirely exhausted, and the running programs are using the harddisk as fallback memory, which is very slow.
A program is doing heavy I/O.
You may be copying a large file, for instance. The program that is doing the copying is requesting lots of data from the harddrive, but while it’s doing this the cpu is actually waiting for this data to be read from the harddrive, blocking access to other programs.
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