Reviews / articles about OS/2 |
Operating systems: ArcaOS, eComStation, IBM OS/2 Warp |
|
|
|
|
DATE: 2005-12-09 21:45:12 AUTHOR: eCo Software
Every modern operating system has its own file system, eComStation is no exception. JFS (Journaling File System) is a native file system for eComstation. What does "Journaling" mean? This file system uses a special area on the disk (named "journal") which is used to write changes which occur during operation. Usage of the journal allows a significant decrease in time of data update and increases filesystem reliability. Modern versions of the JFS filesystem were developed by IBM corporation for OS/2 Warp Server for e-Business. Later it was ported to IBM AIX and Linux. The goal of the developers was to provide high performance, reliability, and scalability on SMP machines. eComtation developers aspire to follow the goals defined by IBM corporation and have continued the development of the JFS filesystem since 2001. Innovations implemented towards the fall of 2005:
Installation of eComStation on JFS volume You can install eComStation on a bootable JFS volume using the OS installer. eComStation may be installed on any DOS-compatible volume. The installation procedure does not differ from installation to an HPFS partition.
Looking at the diagram, you can see the speed of the operating system boot to graphic and text modes, the speed of loading some popular applications. Thus, you can be assured that JFS gives gains up to 100% in comparison with HPFS filesystem. The only thing that it is necessary to achieve these performance gains is to install the operating system onto a bootable JFS volume. Why does launching and operating speed increase? Cache is the reason. Thanks to the fact that system INI and DLL files are placed on a JFS volume, JFS.IFS driver caches them much more efficiently than the HPFS filesystem does. All calls from applications to system libraries require less time because the libraries reside in cache (memory). JFS service utilities
It is worth mentioning one detail, that JFS does not keep data about deleted directories and names of deleted files. This complicates the search for the deleted file. Using JUne it is possible to search for needed or deleted files using a filter, by date, or by extended attributes (EA). Besides that, we recommend you to start a special REXX script regularly, it copies filenames into extended attributes. JUne will show this information during it's file search process. This way, most files will get a name and you can find the necessary file faster. Flash drives with JFS filesystem Flash drive formatting is similar to formatting an ordinary disk. The flash drive must be partitioned, i.e. it is necessary to create an LVM volume first, then format it with JFS. If a drive letter was assigned, then on another computer it will stay the same (if possible). Does JFS have any limitations ? The JFS filesystem was designed in response to modern requirements. It has a sufficient margin of safety to work without serious problems for some time.
JFS for eComStation is ready for usage on SMP machines. Today's processor manufacturers have finished the megahertz race and are concentrating on SMP and multi-core systems development. Future plans It is planned to implement dynamic cache in JFS. Unlike the static cache (used in current version), when the size of memory region assigned for caching stays static during all operating time, dynamic cache allows the capture of additional memory if needed and to release it if not needed. This will allow more efficient use of main memory. Memory regions not occupied by cache will be placed at the disposal of applications running at this moment. It is planned to improve service and recover utilities to increase filesystem reliability and develop new utilies such as defrag. Additional information:
Komentarze:
|
|
||||||||||||||||
(C) OS2.GURU 2001-2021
