SparkFS: Difference between revisions

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===Speed===
===Speed===
The speed of accessing compressed files varies from that of normal uncompressed files. While compressing and decompressing files always carries a slight processing overhead, if the archive is stored on a slow storage medium, such as a floppy disk, dealing with compressed files may still actually be faster because of their smaller size. However, adding or removing large numbers of files from an archive is likely to be much slower using a program like SparkFS, because it is a necessary technical requirement for all filing systems that the files or directories being managed retain their integrity after each and every file is added or deleted. Because they do not need to ensure that the archive is valid at every stage of the updating process, programs like Spark or InfoZip can apply all the modifications in one go and perform the bookkeeping functions afterwards, and when a lot of files must be added to or deleted from an archive, these programs become much quicker by comparison.
It is often slower to access compressed files than uncompressed ones, but not always. While compressing and decompressing files always carries a slight processing overhead, if the archive is stored on a slow storage medium such as a floppy disk, dealing with compressed files may actually be faster because of their smaller size.

However, adding or removing large numbers of files from an archive is likely to be much slower using an [[image filing system]] like SparkFS. This is because all filing systems must ensure that the files and directories being managed retain their integrity while each and every file is added or deleted.

By comparison, programs like Spark or InfoZip do not need to ensure that their archives are valid throughout the updating process, so they can add or delete all the files in a single operation and perform the bookkeeping functions afterwards. Consequently, when a lot of files must be added to or deleted from an archive these programs become much quicker by comparison.

Revision as of 13:09, 22 November 2007

SparkFS
Icon:
SparkFS icon
Maintained by: David Pilling
Description: SparkFS is a powerful compression filing system that saves disc space and allows you to use compressed files and programs as easily as uncompressed ones.
OS Restrictions: None
Languages: Dutch, English, French, German
Alternatives: ArcFS
Website: http://pilling.users.netlink.co.uk/spark.html


Compression Filing Systems

Because SparkFS is a full-blown filing system, it makes archive files as easy to access as ordinary directories. To a non-technical user, the only differences are in the access speed (see below), the shape of the 'directory' icon and the fact that files within an archive cannot be renamed. By comparison, compression programs such as Squash, Spark, Infozip and PKZip for DOS do not allow direct access to the contents of a compressed file. The archive must first be decompressed, usually to another location on the hard disk, and thereafter the standard filer tools can be used with it. After any changes have been made, recompressing is a separate stage.

Speed

It is often slower to access compressed files than uncompressed ones, but not always. While compressing and decompressing files always carries a slight processing overhead, if the archive is stored on a slow storage medium such as a floppy disk, dealing with compressed files may actually be faster because of their smaller size.

However, adding or removing large numbers of files from an archive is likely to be much slower using an image filing system like SparkFS. This is because all filing systems must ensure that the files and directories being managed retain their integrity while each and every file is added or deleted.

By comparison, programs like Spark or InfoZip do not need to ensure that their archives are valid throughout the updating process, so they can add or delete all the files in a single operation and perform the bookkeeping functions afterwards. Consequently, when a lot of files must be added to or deleted from an archive these programs become much quicker by comparison.