Preparing to Install Linux ************************** There are several things which you must do before installing MCC interim Linux besides getting the appropriate files and making a bootable root disk. The target machine must have free space which is not included in already allocated partitions. In some cases this means that you must back up your hard disk, create a smaller DOS partition, using the DOS command `FDISK', and restore your DOS files to the new DOS partition. There are procedures which allow you to change the size of a DOS partition without backing up your files, but we do not recommend such procedures. For more information, see README.fdisk. Disk space required for Linux files =================================== You may wish to have a small Linux system with only a few of the MCC interim packages. The following table gives the approximate size required for each package. The exact size depends on the type of file system on which the package is installed; packages usually take up less space on extended(2) file systems. Remember that each file system also uses up a few hundred Kb on each partition, depending on the type of file system. Extended(2) file systems also reserve a percentage of each partition for the superuser; the exact percentage can be selected by an option to `mkfs' and changed by the command `tune2fs'. (The MCC distribution does not allow you to change the 5% default before installation.) The package Base must be installed from the boot floppy before any other packages. The amount of disk space you require depends on what software you intend to install. For all MCC packages (not including extras), you need about 21 Mb, while the extras require another 10 Mb. For the X window system (which is not included in the MCC distribution), you need a further 20 Mb. TeX (which is also not included in the MCC distribution), requires at least 10 Mb more. The source files for all MCC packages (which are also not part of the distribution) require a further 35 Mb. Additionally, you must consider the space you need for work, perhaps an additional 5 or 10 Mb, or 100 Mb or more for large projects. On the other hand, you may plan to have a large system. In that case, you may wish to distribute your files over several partitions. Linux allows you to have up to 16 partitions on a SCSI disk, and up to 64 partitions on an IDE disk. How you divide your disk is up to you, of course, but there are some points you may wish to consider. If you intend to upgrade Linux at some point, it may be convenient to have your development files on a separate partition. In this way, you can make a new file system for the new distribution, and you will not risk having large, unnecessary binaries which you no longer need. I like to have TeX and X386 on a separate partition, since these are not included in MCC distributions. You may like to put the `/usr' subtree on a partition of its own, or `/usr/src'. The directories `/home' and `/tmp' might also have partitions of their own, so that a user (including you) cannot accidentally fill up the system disk. See README.fdisk. Swap space required for Linux ============================= The amount of swap space you require depends on how much memory you have, and on what you intend to do on your system. What we call "swapping" in the Linux world is sometimes called "paging" on other operating systems. If you use the GNU C compiler, you may need 6 Mb of memory to compile one file. If you have only 4 Mb of physical memory, you will also need at least 2 Mb of swap space for that compilation. When GCC compiles a very large function with optimisation, it may need much more memory than this. If you are using X windows, you may need at least 8 Mb of memory in addition to your other requirements. If you have several users (or if you are running large jobs in several windows or on several consoles), you must add up all their requirements for swap space. On the other hand, most people are the sole users of their machines, and many of them do only one or two things at once. In such cases, you might plan on having a total of 8 to 12 Mb if you are not using X windows, or 16 to 20 Mb if you are using X windows and compiling big packages at the same time. Linux can use two kinds of swap areas: swap partitions and swap files. Swap partitions can be used only for swapping. Swap files have the advantage of being easier to create and destroy, but they are less efficient than swap partitions. No swap partition or swap file can contain more than 16384 Kb of usable swap space, so if you need more than this, you must use several partitions or files. MCC interim Linux can create and activate swap partitions during installation, and normally expects you to have a single swap partition, which it inserts into `/etc/fstab', so that it is activated automatically whenever you boot the installed system. If you wish to have more than one swap partition, or a swap file in addition to or instead of a swap partition, you must create them yourself after installation and put the entries manually into `/etc/fstab'.