Datasheet

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Part I ✦ SUSE Linux Basics
The most common way to partition disks for home Linux use is to have one pri-
mary partition for the Linux root partition, a second primary partition for the swap
partition, and then an extended partition for any other (logical) partitions that may
be needed. Using extended and logical partitions grows the amount of total parti-
tions you can have in a system to 16, which is usually more than enough.
Select the Primary partition option and click OK to proceed.
Defining Filesystems
After a primary partition has been created, you need to define the format in which a
filesystem should be created on that partition, its size, and the mount point for that
filesystem. Linux and Unix use the definition of mount points in the same way that
Windows uses drive letters. The advantage with Linux is that the whole system is
hierarchical in nature, and therefore access to data on disks, network drives, and
partitions can be kept under one manageable tree structure.
Swap Partitions
The first partition you need to create is the swap partition. Most modern operating
systems use swap partitions, also referred to as swap space, to support virtual
memory. Virtual memory is a technique for enabling a system to use more memory
than is physically available to the operating system. Processes on the system that
are inactive or are waiting for input are copied from physical memory into swap
space, known as swapping out a process. At this point, the physical memory associ-
ated with those processes can be reused by the operating system. When the pro-
cess can run again, such as when input is available, it is copied from the swap space
back into memory and continues execution. This is known as swapping in a process.
The way in which processes are swapped in and out of memory is simple in theory,
but is triggered by a number of internal metrics that are maintained and constantly
updated by the kernel.
You should always create a swap partition on a Linux or Unix machine as the work-
load on any system can never be fully quantified beforehand and running out of
physical memory without swap space causes processes to crash or be unable to
execute in the first place.
The window to create a filesystem/partition can be quite daunting for new users
(see Figure 1-12). SUSE and the other distributions try to make the process as sim-
ple and usable as possible. Selecting the format of the filesystem is primarily a con-
cern when creating data partitions or for advanced users, as discussed in the next
section. When creating a swap partition, you must select Swap as its format. You
will notice that the mount point will also change to be swap because the swap parti-
tion is not mounted like a data partition but is used internally by the Linux system.
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