• Proceedings of the Korea Information Processing Society Conference
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• 2003.11b
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• pp.1007-1010
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• 2003

Efficient using of web cache is becoming important factor that decide system management efficiency in web-Based system. Cache performance depends heavily on replacement algorithms, which dynamically select a suitable subset of objects for caching in a finite space. However, replacement algorithm on web cache has many differences than traditional replacement algorithm. In this paper, a web-caching algorithm is proposed for efficient operation of web base system. The algorithm is designed based on a divided scope that considered size reference characteristic and heterogeneity on web object. The performance of the algorithm is analyzed with an experiment. With the experiment results, the algorithm is compared with previous replacement algorithms, and its performance is confirmed ith an improvement of response speed.

• Journal of the Korea Society for Simulation
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• v.12 no.2
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• pp.25-34
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• 2003

Because of explosive growth in demand for web-based multimedia applications, proper proxy caching for large multimedia object (especially video) has become needed. For a video object which is much larger in size and has different access characteristics than the traditional web object such as image and text, caching the whole video file as a single web object is not efficient for the proxy cache. In this paper, we propose a proxy caching strategy with the constant-sized segment for video file and an improved proxy cache replacement policy. Through the event-driven simulation under various conditions, we show that our proposal is more efficient than the variable-sized segment strategy which has been proven to have higher hit ratio than other traditional proxy cache strategies.

• IEMEK Journal of Embedded Systems and Applications
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• v.13 no.3
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• pp.109-116
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• 2018

SSDs that are not allowed in-place update within the allocated page cause another allocation of a new page that will replace the previous page at the moment data modification occurs. This intrinsic characteristic of SSDs requires many changes to the existing HDD-based IO theory. In this paper, we conduct a performance comparison of FTL caching strategy in perspective of cache hashing (Global vs. grouped) and caching algorithm (LRU vs. NUR) through a simulation. Experimental results show that in terms of energy consumption for flash operation the grouped management of cache is not suitable and NUR algorithm is superior to LRU algorithm. In particular, we found that the cache hit ratio of LRU algorithm is about 10% point higher than that of NUR algorithm while the energy consumption of LRU algorithm is about 32% high.

• The Transactions of the Korean Institute of Electrical Engineers
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• v.41 no.7
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• pp.784-792
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• 1992

In this paper we design and implement a method for application programs to allow handling of large data files in DOS environment. In this method we use extended memory and hard disk as a data buffer. And we use a part of the conventional DOS memory as a buffer cache which allows the application program to use extended memory and hard disks transparently. Using buffer cache also allows us some speed improvement for the application program.

• The KIPS Transactions:PartC
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• v.9C no.6
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• pp.961-968
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• 2002

This paper proposes a new access method which is to considered the high variability in World Wide Web and manage the web cache space. Instead of using a single cache, we divide a cache and store all documents according to their file types. Proposed method was compares with current cache management policies using LFU, LRU and SIZE base algorithm. Using two different workload, we show the improvement hitting ratio and byte hitting ratio through simulating on the file type caching.

• The KIPS Transactions:PartA
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• v.10A no.2
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• pp.83-92
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• 2003

RAID 5 is a widely-used technique used to construct disk systems of high reliability and performance. This paper proposes APGOC (Adaptive Parity Group On Cache) organization on cache to solve "small write" problem of RAID 5 especially in OLTP (On-Line Transaction Processing System) environments. In our approach, when user process makes a request for a file to kernel, the information on the read/write characteristics is added to the file data structure of the file system. With this information, data and parity cache can be managed interchangeably through parity fetching. Therefore we can enhance the cache utilization and improve the disk request response time. Our method is analyzed and evaluated with a simulation method. Comparing with previous works, we observed about 6~l3% of performance enhancement.hancement.

• The KIPS Transactions:PartA
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• v.14A no.1 s.105
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• pp.55-62
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• 2007

Uptime of embedded processors for mobile devices are dependent on battery consumption. Especially the large portion of power consumption is known to be due to cache management in embedded processors. This paper proposes an energy efficient data cache structure for high performance embedded processors. High performance prefetching data cache issues prefetching instructions before issuing demand-fetch instructions based on reference predictions. These prefetching instruction bring reduction on memory delay by improving cache hit ratio, but on the other hand those increase energy consumption in proportion to the number of prefetching instructions. In this paper, we adopt tag history table on prefetching data cache for reducing energy consumption by minimizing parallel tag comparison. Experimental results show the proposed data cache improves performance on energy consumption as well as memory delay.

• Journal of IKEEE
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• v.28 no.3
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• pp.458-464
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• 2024

This study proposes a fault-tolerant caching system to address the issue of caching content imbalance caused by the dynamic departure and participation of cache servers in a heterogeneous cache server network, and validates it in both real and virtual environments. With the increase of large-scale media content requiring various types and resolutions, the necessity of cache servers as key components to reduce response time to user requests and alleviate network load has been growing. In particular, research on heterogeneous cache server networks utilizing edge computing and low-power devices has been actively conducted recently. However, in such environments, the irregular departure and participation of cache servers can occur frequently, leading to content imbalance among the cache servers deployed in the network, which can degrade the performance of the cache server network. The fault-tolerant caching algorithm proposed in this study ensures stable service quality by maintaining balance among media contents even when cache servers depart. Experimental results confirmed that the proposed algorithm effectively maintains content distribution despite the departure of cache servers. Additionally, we built a network composed of seven heterogeneous cache servers to verify the practicality of the proposed caching system and demonstrated its performance and scalability through a large-scale cache server network in a virtual environment.

• KIISE Transactions on Computing Practices
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• v.21 no.8
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• pp.543-548
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• 2015

Recently, volume of data has been growing dramatically along with the growth of social media and digital devices. However, the existing disk-based distributed file systems have limits to their performance of data processing or data access, due to I/O processing costs and bottlenecks. To solve this problem, the caching technique is being used to manage data in the memory. In this paper, we propose a cache management scheme to handle load balancing in a distributed memory environment. The proposed scheme distributes the data according to the memory size, n distributed environments with different memory sizes. If overloaded nodes occur, it redistributes the the access time of the caching data. In order to show the superiority of the proposed scheme, we compare it with an existing distributed cache management scheme through performance evaluation.

• The KIPS Transactions:PartA
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• v.11A no.1
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• pp.29-36
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• 2004

As the number of Internet users and the amount of web contents have increased very fast, reducing the load of web servers and providing web services more rapidly have been great issues. A web-cache system, which is located between the user and the web server, has been used by many web service providers as an effective way to reduce the load of web servers and the web service response time. In this paper, we have developed a web-cache system which is based on the Squid cache and has a compression capability. The web-cache system in which compression capability reduces the amount of network traffic and the web service response time by transfering the web contents in the compressed format over the network between the web-cache system and the user. The performance enhancement is greater in the reverse-cache system than in the forward-cache system because in the case of the reverse-cache system, the cache reduces the amount of traffic on the Internet which is the bottleneck in the network path between the user and the web server. The experimentation result shows that the amount of data traffic has reduced from 2 to 8 times depending on the size of the web contents. The web server response time has reduced 37% on the average and when the size of the web content is greater than 10Kbyte, the response time has reduced 87% on the average.