lower-level communication protocol 中文意思是什麼
lower-level communication protocol
解釋
較低層通信協議- lower : adj 〈low 的比較級〉1 較低的。2 下級的,低級的。 lower animals 下等動物。3 南部的。 in lower Manh...
- level : n 1 水平儀,水準儀;水準測量。2 水平線,水平面;水平狀態;平面,平地。3 水平,水準;水位;標準;...
- communication : n. 1. 通訊,通知;交換;信息;書信,口信,通報。2. 傳達,傳授;傳播;傳染。3. 交通,交通機關;聯系,連絡(設備)。4. 【宗教】接受聖餐。
- protocol : n 1 議定書;調查書,始末記。2 (條約等的)草案,草約;(羅馬教皇詔書等的)首尾程式。3 〈the P 〉 ...
-
The hierarchy of controlling instruments, from higher to lower, is application program, platform, the instruments driver dll, visa, operating system and protocol level of the communication
平臺的上層是測試應用程序,平臺以下有儀器驅動層、 visa層、操作系統層和通訊協議層。 -
As the application of distributed computing is used much more widely , distributed database becomes a significant part of information management it avoids a lot of disadvantages of conventional centralized database , and is applicable to many situations distributed database is a set of data which is the unity logic , but in fact these data is located on different sites it is of high availability , easy expansibility , high concurrency , high efficiency and etc in distributed system , data redundancy is a method to improve the speed of query and the availability of system distributed query should shield the lower level details of data redundancy from end users , distributed transaction should ensure data from disaccord this paper introduces basic conceptions of distributed database firstly , discusses distributed transaction and concurrent control , describes the development prototype mysql ’ s characters , architecture and executive mechanism , then shows the skeleton model of dpsql and exposes the strategy and algorithm of distributed query and distributed transaction , at last analyzes the extra expenses and response delay of distributed processes this paper exposes the implementation mechanism of distributed query and distributed transaction emphatically distributed query uses the strategy of “ read one , write a11 ” s0 in such a system if user ’ s requests are read - - only for the most part and the distribution of data redundancy is plausible , efficiency is very high distributed transaction uses two - 。 phase commit protocol to ensure the consistency of global data , which has less communication overhead
分散式查詢需要向用戶屏蔽數據冗餘分散的底層細節,分散式事務處理要保證全局數據完整,這都是傳統集中式數據庫不曾面臨的問題。本文首先介紹了分散式數據庫的概念性問題;接著討論了分散式事務涉及的定義及演算法;然後描述了dpsql的原型mysql的特性、結構和執行機制;繼而給出了dpsql的梗概模型,闡述了實現分散式查詢和分散式事務處理的策略及演算法;最後分析了進行分散式處理給系統增加的額外開銷和客戶端的額外響應延遲。本文重點描述了分散式查詢和分散式事務處理的實現機制,分散式查詢採用」讀一個寫全部」的本地優先策略,在讀操作頻繁的系統中,只要庫的分佈合理,單機效率極高,幾乎無任何附加開銷和延遲,而以整個系統的角度看來,吞吐量就更是優于單機系統;分散式事務處理採用兩階段提交協議,通信次數較少並能確實保證副本一致。
分享友人