Configuring Your Partitions
Some of the data is based on our own experience, so you may disagreewith some points. That's fine, your system and needs may require different methods. However, this system does work,and will at least supply you with more information.
You should have a boot/system partition, an application partitionand one or more data partitions. The boot partition will hold Windows NT and the primary paging file; the applicationpartition will hold all other programs, except those which must be installed on the system partition. All otherfiles, whenever possible, should go to your data partitions.
If you have the disk space, it is a good idea to create at least threedata partitions: one for archive data, one for volatile data and one for other data. This will save a lot of backuptime. The boot and program partitions only need to be backed up after initial installation and on those rare occasionswhen you install a Windows NT Service Pack or upgrade, or when you install a new application. The same is trueof the archive partition, because that is where you would put data that is not likely to change (lookup tablesand such). By volatile data we mean temp files and work files, which change very frequently, which you do not needto back up. So, the only partitions that require frequent backups are the ones for "other data". Thissimplifies things and the easier and the faster the backup procedure is, the more frequently you can back up.
The other reason for this scheme is that when data loss or corruptionoccurs, it is almost always because of a bad write to the partition. If 99% of the writing is being done to onepartition, then the chance of corrupting the other partitions is reduced by 99%. If this one partition only containsdata (which has been backed up) and no program files, then losing the partition or a file is not very damagingor important; it is not going to make your machine unbootable, so recovery is easy.
Of course, you can have more than one partition of any of these types.
Now, as to size, the boot/system partition should be at least 400MB,plus the size of your paging file. You can put the paging file in a partition of its own, but that is not vital.We have run systems both ways, and have not noticed any difference, but the advantage of putting the paging fileon the system partition is that you can move it to another partition if later you need more space for the system.(We once had a 250MB system partition, and could not install Windows NT 4.0 Service Pack 3 because we had only50MB free ¾ the installation program said, "Insufficient free space". We then had to reformatand reinstall the entire system.)
The size of the application partition depends on your applications.Figure the approximate size of your application files, not counting data files you can put on data partitions,or applications which must be installed on the system partition. Include space for any new applications you planto add. Now add free space by multiplying your total by some value between 1 1/3 and 2, so that the partition willbe around 50% to 75% full. Plenty of free space means faster I/O, so if you can spare the disk space, go for 50%free.
The data partitions use the remainder of your disk space. How youconfigure them (which format, what size, what volume type) depends on several factors:
Amount of data
Type of format
Data recoverability
Security
Disk space available
To divide your data as suggested above, you need to figure out howmuch space will be used by each type of data. Always leave a generous amount of free space, preferably 50%, sincespeed of access is most important on data files, especially those that are most frequently accessed.
The boot partition should probably be FAT format, but the other partitionscan be FAT or NTFS. See the articles FAT versus NTFS, More Data on Partitions and Multiple Boot Systems for informationon selecting which format to use.
NTFS has its own built-in sector recovery, in the event of a disksector going bad, but data recovery depends on fault-tolerance. See the article Data Recovery for details, butfor our purposes now, fault-tolerance requires Windows NT Server, NTFS format, and more than one physical disk,which increases the amount of disk space needed. For example, a mirror set keeps multiple copies of each file,one on each partition in the set.
To implement the Windows NT security features, you must use the NTFSformat; these features just don't exist for FAT. Aside from the disk format, security is not a factor in configuringpartitions.
Probably the most important factor is disk space; you only have acertain amount to work with. But don't make the mistake of not considering alternatives just because they requireadding hard drives. The prices of IDE disks are dropping rapidly; we recently saw a new major-brand 4GB disk for$274.00. SCSI is more expensive, but even so, mass storage really has become cheap. When you consider the expenseof recovering corrupted data (How many man-hours to restore the data? How much income is lost because the dataor system is unavailable?), one single recovery event would probably cost more than the additional disk that wouldhave prevented the data loss in the first place.
There are a few minor points worth mentioning. Bear in mind that,aside from the boot/system partition, you can change partitions pretty easily. A FAT partition can be convertedto NTFS (but not NTFS to FAT) without having to back up or restore the data. Even so, always, always do a fullbackup before converting, or doing anything that could corrupt data. Although Windows NT cannot change a partitionsize without erasing all of the data, there are programs that allow you to change partition sizes without losingthe data. Be warned that these programs are dangerous because they are powerful; if you make a mistake, you canwipe out the whole disk. Back up first! The point here is that whatever configuration you choose, it can be changedif needed.
None of this is a concern for defragmenting; Diskeeper and DiskeeperLite will defragment all Windows NT-supported partitions safely.
Aside from details applying to special cases (like applications thatrequire their data files to be in the same folder as the program), that's about all there is to configuring yourdisks. It's really pretty simple, given the basic data.
If you have any comments about this article orany requests for new technical articles e-mail
Executive Software Europe
