ArchitectureDescription

MiSim architecture descriptions consist out of a list of microservice descriptions and an optional definition of default Network latency.

{
    "network_latency": <Distribution Experssion>,
    "microservices": [
        List<Microservice Description>
    ]
}

Distribution Expression

To model distributions, MiSim supports a simple distribution expression. It shapes a normal distribution with a mean and a standard deviation. Optionally, the left and right deviation can be specified separately.

Type	Formula	Example
Constant	<const>	"42"
Normal Distribution	<mean>+-<std>	"42+-3"
Skewed Distribution	<mean>+<leftDeviation>-<rightDeviation>	"42+1-3"

Microservice Description

Property	Description
name	The name of the microservice
instances	The number of starting instances of the microservice
capacity	Capacity of each instance
loadbalancer_strategy	The load balancing strategies to use.*
patterns	List of instance owned pattern descriptions that should be used.*
s_patterns	List of service owned pattern descriptions that should be used.*
operations	List of operation descriptions

* See Supported Resilience Mechanisms.

Example

{
    "name": "MyMicroservice",
    "instances": 1,
    "capacity": 1000,
    "loadbalancer_strategy": "round_robin",
    "patterns": [
        List<Pattern Description>
    ],
    "s_patterns": [
        List<Pattern Description>
    ],
    "operations": [
        List<Operation Description>
    ]
}

Operation Description

Property	Description
name	The name of the operation.
demand	The computational demand of the operation.
dependencies	List of Dependencies descriptions.

Example

{
    "name": "MyOperation",
    "demand": 1000,
    "dependencies": [
        List<Dependency Description>
    ]
}

Dependency Description

Property	Description
service	Target service name
operation	Target operation name
probability	Probability of the dependency to be executed.
custom_delay	Custom latency to be used. Overrides default network latency
alternativeProbability	Probability of the dependency to be selected as alternative.
iterations	Number of repetitions for the execution of subordinate dependencies.
type	Can be alternative, loop, or basic (default).

Note that dependencies can be nested with alternatives and loops as intermediate dependencies. Service and operation name can also be combined as fully qualified name in the operation property, e.g., "service.operation".

Examples

{
    "service": "MyService",
    "operation": "MyOperation",
    "probability": 0.5,
    "custom_delay": <Distribution Expression>
}

{
    "name": "INTERNAL_DEP2",
    "demand": 1,
    "dependencies": [
        {
    	"type": "alternative",
    	"dependencies": [
        	{
			"service": "example-service",
			"operation": "example-service.get",
			"alternativeProbability": "0.8"
		},
		{
			"service": "example-service2",
			"operation": "example-service2.get2",
			"alternativeProbability": "0.2"
		}
		]
	}
	]
}

{
    "name": "INTERNAL_DEP",
    "demand": 1,
    "dependencies": [
	{
		"type": "loop",
		"iterations": "2", 
		"dependencies": [
		{
				"service": "gateway",
				"operation": "INTERNAL_DEP2"
		}
		]
	}
	]
}