2,883 research outputs found
Predictive Analysis for Cloud Infrastructure Metrics
In a cloud computing environment, enterprises have the flexibility to request resources according to their application demands. This elastic feature of cloud computing makes it an attractive option for enterprises to host their applications on the cloud. Cloud providers usually exploit this elasticity by auto-scaling the application resources for quality assurance. However, there is a setup-time delay that may take minutes between the demand for a new resource and it being prepared for utilization. This causes the static resource provisioning techniques, which request allocation of a new resource only when the application breaches a specific threshold, to be slow and inefficient for the resource allocation task. To overcome this limitation, it is important to foresee the upcoming resource demand for an application before it becomes overloaded and trigger resource allocation in advance to allow setup time for the newly allocated resource. Machine learning techniques like time-series forecasting can be leveraged to provide promising results for dynamic resource allocation.
In this research project, I developed a predictive analysis model for dynamic resource provisioning for cloud infrastructure. The researched solution demonstrates that it can predict the upcoming workload for various cloud infrastructure metrics upto 4 hours in future to allow allocation of virtual machines in advance
Burst-aware predictive autoscaling for containerized microservices
Autoscaling methods are used for cloud-hosted applications to dynamically scale the allocated resources for guaranteeing Quality-of-Service (QoS). The public-facing application serves dynamic workloads, which contain bursts and pose challenges for autoscaling methods to ensure application performance. Existing State-of-the-art autoscaling methods are burst-oblivious to determine and provision the appropriate resources. For dynamic workloads, it is hard to detect and handle bursts online for maintaining application performance. In this article, we propose a novel burst-aware autoscaling method which detects burst in dynamic workloads using workload forecasting, resource prediction, and scaling decision making while minimizing response time service-level objectives (SLO) violations. We evaluated our approach through a trace-driven simulation, using multiple synthetic and realistic bursty workloads for containerized microservices, improving performance when comparing against existing state-of-the-art autoscaling methods. Such experiments show an increase of Ă— 1.09 in total processed requests, a reduction of Ă— 5.17 for SLO violations, and an increase of Ă— 0.767 cost as compared to the baseline method.This work was partially supported by the European Research Council (ERC) under the EU Horizon 2020 programme (GA 639595), the Spanish Ministry of Economy, Industry and Competitiveness (TIN2015-65316-P and IJCI2016-27485) and the Generalitat de Catalunya (2014-SGR-1051).Peer ReviewedPostprint (author's final draft
Power Management Techniques for Data Centers: A Survey
With growing use of internet and exponential growth in amount of data to be
stored and processed (known as 'big data'), the size of data centers has
greatly increased. This, however, has resulted in significant increase in the
power consumption of the data centers. For this reason, managing power
consumption of data centers has become essential. In this paper, we highlight
the need of achieving energy efficiency in data centers and survey several
recent architectural techniques designed for power management of data centers.
We also present a classification of these techniques based on their
characteristics. This paper aims to provide insights into the techniques for
improving energy efficiency of data centers and encourage the designers to
invent novel solutions for managing the large power dissipation of data
centers.Comment: Keywords: Data Centers, Power Management, Low-power Design, Energy
Efficiency, Green Computing, DVFS, Server Consolidatio
Data-Driven Methods for Data Center Operations Support
During the last decade, cloud technologies have been evolving at
an impressive pace, such that we are now living in a cloud-native
era where developers can leverage on an unprecedented landscape
of (possibly managed) services for orchestration, compute, storage,
load-balancing, monitoring, etc. The possibility to have on-demand
access to a diverse set of configurable virtualized resources allows
for building more elastic, flexible and highly-resilient distributed
applications. Behind the scenes, cloud providers sustain the heavy
burden of maintaining the underlying infrastructures, consisting in
large-scale distributed systems, partitioned and replicated among
many geographically dislocated data centers to guarantee scalability,
robustness to failures, high availability and low latency. The larger the
scale, the more cloud providers have to deal with complex interactions
among the various components, such that monitoring, diagnosing and
troubleshooting issues become incredibly daunting tasks.
To keep up with these challenges, development and operations
practices have undergone significant transformations, especially in
terms of improving the automations that make releasing new software,
and responding to unforeseen issues, faster and sustainable at scale.
The resulting paradigm is nowadays referred to as DevOps. However,
while such automations can be very sophisticated, traditional DevOps
practices fundamentally rely on reactive mechanisms, that typically
require careful manual tuning and supervision from human experts.
To minimize the risk of outages—and the related costs—it is crucial to
provide DevOps teams with suitable tools that can enable a proactive
approach to data center operations.
This work presents a comprehensive data-driven framework to address
the most relevant problems that can be experienced in large-scale
distributed cloud infrastructures. These environments are indeed characterized
by a very large availability of diverse data, collected at each
level of the stack, such as: time-series (e.g., physical host measurements,
virtual machine or container metrics, networking components
logs, application KPIs); graphs (e.g., network topologies, fault graphs
reporting dependencies among hardware and software components,
performance issues propagation networks); and text (e.g., source code,
system logs, version control system history, code review feedbacks).
Such data are also typically updated with relatively high frequency,
and subject to distribution drifts caused by continuous configuration
changes to the underlying infrastructure. In such a highly dynamic scenario,
traditional model-driven approaches alone may be inadequate
at capturing the complexity of the interactions among system components. DevOps teams would certainly benefit from having robust
data-driven methods to support their decisions based on historical
information. For instance, effective anomaly detection capabilities may
also help in conducting more precise and efficient root-cause analysis.
Also, leveraging on accurate forecasting and intelligent control
strategies would improve resource management.
Given their ability to deal with high-dimensional, complex data,
Deep Learning-based methods are the most straightforward option for
the realization of the aforementioned support tools. On the other hand,
because of their complexity, this kind of models often requires huge
processing power, and suitable hardware, to be operated effectively
at scale. These aspects must be carefully addressed when applying
such methods in the context of data center operations. Automated
operations approaches must be dependable and cost-efficient, not to
degrade the services they are built to improve.
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A Reliable and Cost-Efficient Auto-Scaling System for Web Applications Using Heterogeneous Spot Instances
Cloud providers sell their idle capacity on markets through an auction-like
mechanism to increase their return on investment. The instances sold in this
way are called spot instances. In spite that spot instances are usually 90%
cheaper than on-demand instances, they can be terminated by provider when their
bidding prices are lower than market prices. Thus, they are largely used to
provision fault-tolerant applications only. In this paper, we explore how to
utilize spot instances to provision web applications, which are usually
considered availability-critical. The idea is to take advantage of differences
in price among various types of spot instances to reach both high availability
and significant cost saving. We first propose a fault-tolerant model for web
applications provisioned by spot instances. Based on that, we devise novel
auto-scaling polices for hourly billed cloud markets. We implemented the
proposed model and policies both on a simulation testbed for repeatable
validation and Amazon EC2. The experiments on the simulation testbed and the
real platform against the benchmarks show that the proposed approach can
greatly reduce resource cost and still achieve satisfactory Quality of Service
(QoS) in terms of response time and availability
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