Database Reference
In-Depth Information
a
100
R1
R2
R3
R4
95
90
85
80
75
70
00:05
00:05
00:10
00:15
00:20 00:25 00:30
00:35
00:40
00:45
00:50
00:55
01:00
Time
b
R1
R2
R3
R4
100
95
90
85
80
75
70
00:05
00:10
00:15
00:20
00:25
00:30
00:35
00:40
00:45
00:50
00:55
01:00
Time
Fig. 7.13
Comparison of SLA-based vs resource-based database provisioning rules. (
a
) Work-
load: 80/20 (r/w). (
b
) Workload: 50/50 (r/w)
and SLA-based rules is smaller for the workload with the higher write ratio (50/50)
due to the higher contention of CPU resources for the write operations and thus the
conditions of the resource-based rules can be satisfied earlier.
Table
7.2
shows the total number of provisioned database replicas using the
different elasticity rules for the two different workloads. Clearly, while the SLA-
based rules achieves better SLA satisfaction, they may also provision more database
