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Immediate Computable Access to Curated Contributed Data

Webserver Load Model

Source Notebook

Model of a webserver's CPU and memory loads

Examples

Basic Examples (3) 

Retrieve the model:

In[1]:=
ResourceData[\!\(\* TagBox["\"\<Webserver Load Model\>\"", #& , BoxID -> "ResourceTag-Webserver Load Model-Input", AutoDelete->True]\)]
Out[1]=

The icon:

In[2]:=
ResourceData[\!\(\* TagBox["\"\<Webserver Load Model\>\"", #& , BoxID -> "ResourceTag-Webserver Load Model-Input", AutoDelete->True]\), "Icon"]
Out[2]=

The annotation:

In[3]:=
ResourceData[\!\(\* TagBox["\"\<Webserver Load Model\>\"", #& , BoxID -> "ResourceTag-Webserver Load Model-Input", AutoDelete->True]\), "Annotation"]
Out[3]=

Scope & Additional Elements (5) 

Available content elements:

In[4]:=
\!\(\* TagBox[ RowBox[{"ResourceObject", "[", "\"\<Webserver Load Model\>\"", "]"}], #& , BoxID -> "ResourceTag-Webserver Load Model-Input", AutoDelete->True]\)["ContentElements"]
Out[4]=

The transfer function model:

In[5]:=
ResourceData[\!\(\* TagBox["\"\<Webserver Load Model\>\"", #& , BoxID -> "ResourceTag-Webserver Load Model-Input", AutoDelete->True]\), "TransferFunctionModel"]
Out[5]=

The input variables:

In[6]:=
ResourceData[\!\(\* TagBox["\"\<Webserver Load Model\>\"", #& , BoxID -> "ResourceTag-Webserver Load Model-Input", AutoDelete->True]\), "InputVariables"]
Out[6]=

Other variables:

In[7]:=
ResourceData[\!\(\* TagBox["\"\<Webserver Load Model\>\"", #& , BoxID -> "ResourceTag-Webserver Load Model-Input", AutoDelete->True]\), "OtherVariables"]
Out[7]=

Temporal variable:

In[8]:=
ResourceData[\!\(\* TagBox["\"\<Webserver Load Model\>\"", #& , BoxID -> "ResourceTag-Webserver Load Model-Input", AutoDelete->True]\), "TemporalVariable"]
Out[8]=

Visualizations (2) 

The transfer-function model of the system:

In[9]:=
tfm = ResourceData[\!\(\* TagBox["\"\<Webserver Load Model\>\"", #& , BoxID -> "ResourceTag-Webserver Load Model-Input", AutoDelete->True]\), "TransferFunctionModel"]
Out[9]=

The poles are within the unit circle:

In[10]:=
ListPlot[Flatten[ReIm[TransferFunctionPoles[tfm]], 2], Sequence[ Frame -> True, PlotRange -> {{-1.1, 1.1}, {-1.1, 1.1}}, PlotMarkers -> Style[ Rotate["+", Rational[1, 4] Pi], GrayLevel[0], Large], AspectRatio -> 1, Axes -> False, Epilog -> { GrayLevel[0.5], Dashing[{Small, Small}], Circle[{0, 0}, 1]}]]
Out[10]=

Analysis (2) 

A set of values for inputs umr and uka:
In[11]:=
Short[inp = Inner[ConstantArray, {{600, 10}, {800, 15}, {450, 5}}, {300, 700, 500}, Join, 1]]
Out[11]=

Simulate the system's response to the input values:

In[12]:=
OutputResponse[ResourceData[\!\(\* TagBox["\"\<Webserver Load Model\>\"", #& , BoxID -> "ResourceTag-Webserver Load Model-Input", AutoDelete->True]\)], inp]; ListStepPlot[%, DataRange -> {0, 1500}, Sequence[ PlotRange -> All, PlotLegends -> {"\!\(\*SubscriptBox[\(x\), \(cpu\)]\)", "\!\(\*SubscriptBox[\(x\), \(mem\)]\)"}]]
Out[13]=

Suba Thomas, "Webserver Load Model" from the Wolfram Data Repository (2025)  

Data Resource History

  • Date Created:

Source Metadata

  • Citation:
    • Yixin Diao, N. Gandhi, J. L. Hellerstein, S. Parekh and D. M. Tilbury, "Using MIMO feedback control to enforce policies for interrelated metrics with application to the Apache Web server", NOMS 2002.

Publisher Information

  • Prepared for the Wolfram Data Repository By: Maher Kuzbari, Suba Thomas
  • Publisher of Record: Suba Thomas