Queuing Model for Web Workload Characterization

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing resource allocation methods in online systems, such as data centers, struggle to accurately predict web workload fluctuations and account for time-varying traffic intensities, leading to impractical trial-and-error approaches in system management and capacity planning.

Innovation Solution

A method is developed to generate a queuing model using a Markovian Arrival Process (MAP) for web servers, which parameterizes arrival and service times to predict server performance, handling batch requests and different request types, and computes performance metrics like queue length and response time.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Productivity

If traditional trial-and-error methods are used for resource allocation, then system management tasks can be performed, but the process becomes impractical as data centers grow larger and workloads become more complex

Engineering Contradiction:
Improveresource allocation efficiencyVSAvoidsystem complexity
Core Design Contradiction:
ProductivityVSDevice complexity

Solution Approach 1:

The patent creates simplified computational models (queuing models) that copy and represent the complex behavior of large data center systems. These models capture essential workload characteristics and server performance dynamics without requiring full-scale simulations, enabling practical resource allocation decisions for growing systems.

Inventive Principle:
Principle #26Copying

Solution Approach 2:

The patent transforms complex workload characteristics into manageable model parameters through automated fitting procedures. By changing the representation from raw trace data to fitted model parameters, the system can efficiently handle increasing complexity without requiring proportional increases in computational resources or time.

Inventive Principle:
Principle #35Parameter changes

2Measurement precision

If detailed trace data analysis is performed to accurately characterize web workload, then prediction accuracy improves, but the computational complexity and time requirements increase

Engineering Contradiction:
Improveworkload characterization accuracyVSAvoidmodeling time
Core Design Contradiction:
Measurement precisionVSLoss of time

Solution Approach 1:

The patent performs preliminary fitting of queuing models to trace data during an offline phase, creating pre-computed models that capture workload characteristics. These pre-fitted models can then be used for rapid performance prediction without requiring real-time analysis of detailed trace data, significantly reducing online computational time.

Inventive Principle:
Principle #10Preliminary action

Solution Approach 2:

The patent segments the workload characterization process into distinct phases: trace data collection, model fitting, and performance prediction. By separating the computationally intensive fitting phase from the prediction phase, the system achieves both accurate characterization and efficient runtime performance.

Inventive Principle:
Principle #1Segmentation

3Device complexity

If conventional queuing models are used that assume Poisson arrivals and exponential service times, then the models are simple to implement, but they fail to accurately represent real web workload patterns including batch requests and different request types

Engineering Contradiction:
Improvemodel simplicityVSAvoidperformance prediction accuracy
Core Design Contradiction:
Device complexityVSReliability

Solution Approach 1:

The patent generalizes conventional queuing models by changing the arrival process from Poisson to Markovian Arrival Process (MAP) and service time distribution from exponential to general distributions. This parameter change allows the models to capture complex workload patterns like batch requests and different request types while maintaining the analytical tractability needed for practical implementation.

Inventive Principle:
Principle #35Parameter changes

Solution Approach 2:

The patent combines multiple modeling components (MAP for arrivals, general service time distributions, state-dependent service rates) into a composite queuing model. This composite approach integrates various features to accurately represent real web workloads while preserving the mathematical structure needed for performance analysis.

Inventive Principle:
Principle #40Composite materials

Data Source

PatentUS8560618B2Characterizing web workloads for quality of service prediction
Publication Date: 2013.10.15 SAP SE
  • US8560618B2 patent drawing
  • US8560618B2 patent drawing
  • US8560618B2 patent drawing

AI summary

Implementations of the present disclosure provide systems and methods directed to receiving, at a computing device, trace data provided in a trace log file corresponding to a server, parameterizing, using the computing device, a first Markovian Arrival Process (MAP) model based on the trace data, parameterizing, using the computing device, a second MAP model based on the trace data, defining a queuing model that models a performance of the server and that includes the first MAP model and the second MAP model, and storing the queuing model in computer-readable memory.