• Journal of Information Technology Applications and Management
• /
• v.10 no.4
• /
• pp.169-183
• /
• 2003

In multimedia systems, very large files are stored and played. Because those files are read-centric and have low reusability, legacy file systems that are optimized for the use of many small files, do not show good performance in the multimedia systems. We implemented a new file system to deal with those characteristics. The new file system shows the superior performances in read, write and mixed operation to the Linux's EXT2 or EXT3 file systems. The new file system was implemented on the Linux operating system, and it also can be easily ported to other operating systems.

• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.26 no.1
• /
• pp.1-6
• /
• 2022

Recently, IoT sensors are often used to produce stream data locally and they are provided for edge computing applications. Mass-produced data are stored in the mobile device's database for real-time processing and then synchronized with the server when needed. Many mobile databases are developed to support those applications. They are CloudScape, DB2 Everyplace, ASA, PointBase Mobile, etc, and the most widely used database is SQLite3 on Linux. In this paper, we focused on the performance required for synchronization with the server. The search performance required to retrieve SQLite3 was compared and analyzed according to the type of each Linux file system in which the database is stored. Thus, performance differences were checked for each file system according to various search query types, and criteria for applying the more appropriate Linux file system according to the index use environment and table scan environment were prepared and presented.

• The KIPS Transactions:PartA
• /
• v.8A no.4
• /
• pp.359-366
• /
• 2001

This paper overviews the design of SANique$^{TM}$ -a shred file system for Linux cluster based on SAN environment. SANique$^{TM}$ has the capability of transferring user data from network-attached SAN disks to client applcations directly without the control of centralized file server system. The paper also presents the characteristics of each SANique$^{TM}$ subsystem: CFM(Cluster File Manager), CVM(Cluster Volume Manager), CLM(Cluster Lock Manager), CBM(Cluster Buffer Manager) and CRM(Cluster Recovery Manager). Under the SANique$^{TM}$ design layout, then, the syndrome of '||'&'||'quot;split-brain'||'&'||'quot; in shared file system environments is described and defined. The work first generalizes and illustrates possible situations in each of which a shared file system environment may split into two or more pieces of separate brain. Finally, the work describes the SANique$^{TM}$ approach to the given "split-brain"problem using SAN disk named "split-brain" and develops the overall recovery procedure of shared file systems.

• Proceedings of the KIEE Conference
• /
• 2004.07d
• /
• pp.2429-2431
• /
• 2004

In this paper, we have designed a remote controlable HDR System using all embedded linux board. The system is composed of three parts - a HDR System, a PC client program for remote control and a Nameserver for registering and aquisition of the IP address. The system is built in an embedded board using a linux kernel. With the Linux the system can support networking and file system for a hard disk management In addition, the system embeds a web-server and a ftp-server for remote manipulation and file transfer. And the hardwares of the system are controlled by the linux device driver mechanism. MPEG1/2 technique is used to compress TV tuner signal and external analog video/audio signal. And compressed data is stored in a hard disk. The data stored in the system is accesable through lan or internet. And RTP protocol is used to enable the system to service live stream of instant video/audio input.

• Journal of Information Technology Applications and Management
• /
• v.12 no.1
• /
• pp.125-140
• /
• 2005

Nowadays, we have many embedded systems which store and process multimedia data. For multimedia systems using hard disks as storage media such as DVR, existing file systems are not the right choice to store multimedia data in terms of cost. performance and reliability. In this study we designed a reliable file system with very high performance for embedded multimedia applications. The proposed file system runs with quite simple disk layout to reduce time to initialize and to recover after power failures, uses a large data block to speed up the sequential accesses, incorporates a time-based indexing scheme to improve the time-based random accesses and boosts reliability by backing up the important meta data on a small NVRAM. We implemented the file system on a Linux-based DVR and verified the performance by comparing with existing file systems.

• Journal of Advanced Navigation Technology
• /
• v.17 no.1
• /
• pp.39-46
• /
• 2013

If a file system is damaged because of the unusual system close, the system performs the consistency test using fsch and it takes long time. Especially, if it is a big file system, it will take a lot of time. The journaling file system that uses journaling technique, can reduce the restoring time because it uses meta data and it may increase the chance of restoration when restoring. The goal of this paper compared performance evaluation journaling file systems focused on the reading and writing using Iozone tool which is the kernel based benchmarking tool in linux operating system. In this paper, Ex4 which is the current basic Linux file system. is 1.28x faster than XFS file system in terms of file read performance and 1.22x faster than Ext3 file system in terms of file write performance.

• The KIPS Transactions:PartA
• /
• v.17A no.2
• /
• pp.63-72
• /
• 2010

Recently, the need for multimedia devices, such as digital TV, and camcorder has increased. These devices provide many services on multimedia files such as playing, recording, and editing. Throughout these services, in case of storing edited large-scaled multimedia files, existing file system have several capability problems that are taking too much time and requiring disk I/O. In this paper, we propose the use of Linux Ext2 file system based 'Block-Link file (BL-file) system' in order to solve these problems. For the BL-file system, when editing and storing large-scaled files, there is no data input or output but only modification of the metadata. Additionally, by sharing data blocks between multimedia files, we can save disk spaces. Moreover, because the managing of data block sharing information is more convenient than the existing FWAE technique, we can lessen system overhead. The BL-file system is based on Ext2 file system and implemented in a Linux environment, and the usefulness of the proposed technique is validated by applying the Linux multimedia file-editing tool 'Avidemux'.

• Spatial Information Research
• /
• v.10 no.1
• /
• pp.93-106
• /
• 2002

The traditional file system are designed to store and manage fur small size files. So. we cannot process the huge files related with geographic information data using the traditional file system such as unix file system or linux file system. In this paper, we propose new metadata structures and management mechanisms for the large file system in geographic information system. The proposed mechanisms use dynamic multi-level mode for large files and dynamic bitmap for huge file system. We implement the proposed mechanisms in the metadata structures of SANtopia is shared disk huge file system for storage area networks(SAN).

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
• /
• 2014.05a
• /
• pp.355-357
• /
• 2014

Linux environment that is commonly used at embedded systems, supports various file systems as Ext2, FAT, NTFS, ets. The file system that is equiped on the embedded system is mostly implemented on mini hard disk or flash memory. The types of the file system of the system make an effect on the performance of a application programs. The factors of file system performance on a same media are block allocation and block free time. On these factors, block free time is not so different according to the type of file systems. This thesis performs the performance benchmark of a Ext2, FAT and NTFS file systems about block allocation performance. As the result, it is discussed that what file system is better at which case.

• Proceedings of the Korean Information Science Society Conference
• /
• 2001.04a
• /
• pp.100-102
• /
• 2001

Intensive I/O bandwidth demand of the multimedia streaming service puts significant burden on file system. Different from the legacy text based or image data, the semantics of the data in multimedia format can be significantly affected if the data block is not delivered by the predefined deadline. The legacy file system used in Unix or Unix like environment is designed to efficiently handle the files who sizes range from few hundreds of byte to several tens of gigabytes. This fundamental design philosophy results in the file system based on multi level skewed tree structure. Multi level i-node structure has significant drawback when the application performs sequential read operation. In this article, we present the result of the performance study of the file system which is specifically designed for handling multimedia streams. We implemented the file system on Linux Operating System environment and examines the performance behavior of the file system under streaming I/O workload. The result of the study shows that the proposed file system performs much more efficiently than the ext2 file system of Linux does.