Table 2 Notation.

From: Efficient workflow scheduling using an improved multi-objective memetic algorithm in cloud-edge-end collaborative framework

Notation

Definition

\(CS\)

The set of cloud servers

\(ES\)

The set of edge servers

D

The set of terminal devices

\(App\)

The set of applications

\({A_j}\)

The set of j-th applications

\(T_{j}^{i}\)

The i-th task of j-th applications

\({E_j}\)

The adjacent matrix of the dependencies of \({A_j}\)

\(R1_{j}^{i}\)~\(R6_{j}^{i}\)

Resource requirements during task execution

\(R_{x}^{1}\)~\(R_{x}^{6}\)

The resource of server x

\(\varepsilon\)

The proportion of additional server resources occupied by task replicas

\(\{ pre_{j}^{i},sub_{j}^{i}\}\)

The predecessor and successor task sets of \(T_{j}^{i}\)

\(K_{j}^{i}\)

The scheduling strategy of the i-th task of j-th applications

\(TD_{j}^{i}\)

The amount of data transmitted to successor tasks

\(W_{j}^{i}\)

The execution time required for i-th task in j-th application

\(u_{x}^{1}\sim u_{x}^{6}\)

Represent the utilization of resources of the server x

\(\alpha _{i}^{c}\)

Task i is assigned to the n-th cloud server

\(\beta _{i}^{e}\)

Task i is allocated to the m-th edge server

\(TT_{{x,y}}^{{i,j}}\)

Represent the time required to transfer data for task \(T_{j}^{i}\) in application \({A_j}\) from server x to server y

\(TR_{x}^{y}\)

Denote the data transfer rate between servers x and y

\(dis_{x}^{y}\)

Represent the transmission distance between x and y

\(TS_{x}^{y}\)

Indicate the transmission speed

\(ST_{{}}^{{i,j}}\)

Start time of the \(T_{j}^{i}\)

\(FT_{{}}^{{i,j}}\)

Finish time of the \(T_{j}^{i}\)