Performance Attributes Reference¶
This page documents the PLEXOS Performance class attributes and their default values, validation rules, and descriptions.
To look at the open access PLEXOS documentation, go to PLEXOS Performance Index.
Use this reference when setting configuration values through PlexosDB
attributes, for example with add_attribute, get_attribute, and
list_attributes.
Performance Attributes¶
Name |
Units |
Default Value |
Validation Rule |
Description |
|---|---|---|---|---|
Barrier Convergence Tolerance |
- |
1E-08 |
Between 0 And 1 |
Termination criteria for the Barrier algorithm |
Carry over MIP Time |
Yes/No |
0 |
In (0,-1) |
If unused MIP Max Time is carried over to the next MIP solve allowing more time on harder problems |
Cold Start Optimizer 1 |
- |
0 |
In (0,1,4,5,6,9,10) |
First priority optimizer used to solve problems from a cold-start. |
Cold Start Optimizer 2 |
- |
0 |
In (0,1,4,5,6) |
Second priority optimizer used to solve problems from a cold-start. |
Cold Start Optimizer 3 |
- |
0 |
In (0,1,4,5,6) |
Third priority optimizer used to solve problems from a cold-start. |
Concurrent Mode |
- |
0 |
In (0,1) |
Mode for the concurrent optimizer |
Crossover |
Yes/No |
-1 |
In (0,-1) |
If crossover is used to transform the interior solution produced by barrier into a basic solution |
Feasibility Repair Failure |
- |
0 |
In (0,1) |
Action to take if an infeasible problem cannot be repaired. |
Feasibility Tolerance |
- |
0 |
>= 0 |
Allowable violation of variable bounds (0 = solver default value) |
Hint Mode |
- |
0 |
In (0,1,2) |
Controls how variable hints are used by the solver |
Hot Start Optimizer 1 |
- |
0 |
In (0,1,4,5,6,9,10) |
First priority optimizer used to solve problems from a hot-start. |
Hot Start Optimizer 2 |
- |
0 |
In (0,1,4,5,6) |
Second priority optimizer used to solve problems from a hot-start. |
Hot Start Optimizer 3 |
- |
0 |
In (0,1,4,5,6) |
Third priority optimizer used to solve problems from a hot-start. |
Maximum Monitored MIP Iterations |
- |
-1 |
Maximum number of monitored row/column iterations with MIP enabled |
|
Maximum Parallel Tasks |
- |
-1 |
>= -1 |
Maximum number of parallel optimizations run concurrently, where -1 means one task per CPU. |
Maximum Threads |
- |
-1 |
>= -1 |
Maximum number of threads used simultaneously by all simplex and interior point optimizers, where -1 means all available threads. |
MIP Absolute Gap |
- |
0 |
>= 0 |
Absolute tolerance on the gap between the best integer objective and the objective of the best node remaining |
MIP Focus |
- |
0 |
In (0,1,2,3) |
High-level solution strategy for the MIP solver |
MIP Hard Stop |
s |
-1 |
>= -1 |
Hard limit on the mixed integer programming time when using MIP Max Relative Gap and MIP Max Time is a soft limit |
MIP Improve Start Gap |
- |
0 |
>= 0 |
Switch strategy to improving the best integer solution when this gap is reached. |
MIP Interrupt |
Yes/No |
0 |
In (0,-1) |
If the MIP search can be interrupted by pressing the CTRL-P key combination |
MIP Max Absolute Gap |
- |
0 |
>= 0 |
When set to a value greater than zero, the MIP Max Time is treated as a soft constraint with optimization continuing until the MIP Max Absolute Gap is reached. |
MIP Max Relative Gap |
- |
0 |
>= 0 |
When set to a value greater than zero, the MIP Max Time is treated as a soft constraint with optimization continuing until the MIP Max Relative Gap is reached. |
MIP Max Relaxation Repair Time |
s |
-1 |
>= -1 |
Maximum time allowed in repairing an infeasible mixed integer programming problem |
MIP Max Time |
s |
-1 |
>= -1 |
Maximum time in mixed integer programming algorithm |
MIP Max Time with Carry over |
s |
-1 |
>= -1 |
Maximum time in mixed integer programming algorithm including any unused time carried over |
MIP Maximum Threads |
- |
-1 |
>= -1 |
Maximum number of threads used by the mixed integer optimizer, where -1 means all available threads. |
MIP Node Optimizer |
- |
0 |
In (0,1,4,5,6,9,10) |
Optimizer used at the nodes of the branch and bound algorithm. |
MIP Relative Gap |
- |
0.0001 |
>= 0 |
Declare the integer solution optimal when this gap is reached between the current integer solution and best-bound linear relaxation (this is not a measure of optimality). |
MIP Root Optimizer |
- |
0 |
In (0,1,4,5,6,9,10) |
Optimizer used to solve the linear relaxation of a mixed-integer program. |
MIP Start Solution |
- |
1 |
Between 0 And 2 |
MIP solver will be warm started with previous solutions according to this setting. |
Monitoring Maximum Threads |
- |
-1 |
>= -1 |
Maximum number of threads for monitored constraint iterations, where -1 means all available threads. |
Monitoring Periodic Clearing |
- |
0 |
>= 0 |
Clear monitored constraints and variables from the formulation periodically (number of steps) |
Objective Scalar |
- |
1 |
> 0 |
Scale the objective function internally by this factor |
Objective Tolerance |
- |
0 |
>= 0 |
Smallest allowable objective function coefficient |
Optimality Tolerance |
- |
0 |
>= 0 |
Optimality tolerance (0 = solver default value) |
Presolve |
Yes/No |
-1 |
In (0,-1) |
Toggles on/off solver presolve |
Random Number Seed |
- |
0 |
Between 0 And 2000000000 |
Random number seed for the solver |
Scaling |
Yes/No |
-1 |
In (0,-1) |
Toggles on/off solver problem scaling |
Small LP Nonzero Count |
- |
250000 |
> 0 |
Maximum number of non-zeros in a ‘small’ linear programming problem. |
Small LP Optimizer |
- |
0 |
Between 0 And 9 |
Optimizer used to solve ‘small’ liner programming problems. |
SOLVER |
- |
4 |
In (0,1,2,3,4,6,7,8) |
SOLVER engine used by PLEXOS. |
Sparsify |
- |
-1 |
In (-1,0,1,2) |
Strategy for matrix sparsification during presolve |