摘要(中) |
由於網際網路的蓬勃發展,使用網路服務的人口迅速地增加,因此必須使用 更多的伺服器(Application Server)同時提供服務,來滿足大量的服務需求。但 相對的,同時使用多台伺服器若不能有效地提供負載平衡(load balancing),會 造成有些伺服器過載或者閒置,因而導致服務品質的不佳。系統中伺服器個數的 多寡將是資源配置的主要考慮因素,因此,該如何在資源有限的情況下發揮最大 的經濟效益,一直都是企業營運的目標之一。
本研究目的是以 LAPO(Load Adjusted Profile Oriented User Allocation Algorithm)演算法改善 POCA(Profile Oriented Clustering Algorithm)演算法在求 取最佳組合解時,必須耗費大量的計算時間,以及能對使用者在 Application server 分配上更均勻,確實達到 load balancing 之目的。由於 LAPO 在有設置條件的情況 下,能有效的掌控 Application server 所分配的使用者個數,因此能減少計算最佳 組合解的次數,有效地增進執行效率。實驗數據來自 SAP ERP ECC 6.0 系統,並 且在實際驗證過後,確定 LAPO 的效率較好、結果更符合企業運用的實際情境。
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