Performance Parameters for Parallel Databases

Parameters for Parallel Databases

Some parameters to judge the performance of Parallel Databases are:
1. Response time: It is the time taken to complete a single task for given time.

2. Speed up in Parallel database:

• Speed up is the process of  increasing degree of (resources) parallelism to complete a running task in less time.
• The time required for running task is inversely proportional to number of resources.

Formula:
Speed up = T_S / T_L
Where,
     T_S = Time required to execute task of size Q
     T_L = Time required to execute task of size N*Q



• Linear speed-up is N (Number of resources).
• Speed-up is sub-linear if speed-up is less than N.

3. Scale up in Parallel database:
Scale-up is the ability to keep performance constant, when number of process and resources increases proportionally.

Formula:
Let Q be the Task and Q_N the task where N is greater than Q
T_S = Execution time of task Q on smaller machine M_S
T_L = Execution time of task Q on smaller machine M_L

Scale Up = T_S /T_L