Energy-Aware Disk Storage Management : Online Approach with Application in DBMS

Abstract

Energy consumption has become a first-class optimization goal in design and implementation of data

MQHD: Dynamic Load Balancing Method for Energy-Aware Storage Systems

“…If the disk's request arrival speed exceeds the overload threshold, the data block will be exchanged until the disk's request arrival speed is less than or equal to the target threshold. WAM can always make the request arrival speed of the hot disk less than or equal to the target threshold, but the exchange only occurs when the request arrives at the disk, and only the requested data block is exchanged at a time, which makes it difficult to quickly and effectively eliminate the overload state of the hot disk [8].…”

“…e closer the coefficient is to 1, the more the accesses are centralized on partial disks. For a specified disk, the Zipf distribution formula is used to calculate its assessed probability, as shown in equation (8). Data popularity is similar to disk popularity in meaning, indicating the degree of concentration of data is accessed.…”

“…As shown in Figure 7(a), when disk overload occurred at the beginning of the 212 requests, PDC did not perform load adjustment in time. PDC did not perform load adjustment until about 300 requests, when the timing migration time arrived, which had caused a large number of requests to be (1) procedure LOADBALANCING (2) while L(i) > OL do (3) if i flag(i) � 1 then c(i) ⟵ 0.9 × c(i); (4) k(i) ⟵ 0.8; (5) i flag(i) ⟵ 0; (6) o flag(i) ⟵ 1; (7) α(i) ⟵ (L(i) − OL/L(i)) × 100%; (8) LPR(i) ⟵ c(i) × α(i); (9) min ⟵ 1 (10) for j � 2 to n do (11) if L(j) < L(min) then min ⟵ j; (12) end for When disk overload occurs, for each request that arrived at the disk, WAM locates the data block of the request after servicing it and then exchanges the data block with an unaccessed data block of an unoverloaded disk. Such an exchange will continue until the disk's request arrival speed is less than or equal to the target threshold.…”