Is over-capacity inevitable in cloud computing?
A lot of discussion is going on these days around some performance issues that Amazon customers are suffering with the Elastic Computing Cloud (EC2).
The discussion was triggered by Alan Williamson, a prominent voice in the Java community, who posted an interesting description of his 3-years experience with EC2.
Williamson suggests that Amazon is allowing EC2 over-subscription at the point that the cloud is so crowded to generate some serious latency in the internal network, which impacts on the performance of any multi-tier application that resides on multiple virtual machines.
Another Amazon customer, David Mok, CTO at OleOle.com, suggests instead that the overall performance degradation depends on some differences (the CPU) in the physical hardware that is below the cloud, and that the cloud platform, the Amazon implementation of Xen, is incapable to fully abstract.
Christopher Hoff, former Chief Security Architect at Unisys and now Director of Cloud and Virtualization Solutions at Cisco, jumps in to comment the whole thing.
His very interesting point is that over-subscription is perfectly normal – modern networks are designed around such model – while over-capacity is an issue that we are going to have with cloud computing as much as we already have it with telecom networks.
He goes one highlighting that at today in cloud computing there’s nothing like a throughput SLA because:
…Your virtual interface ultimately is bundled together in aggregate with other tenants colocated on the same physical host and competes for a share of pipe (usually one or more single or trunked 1Gb/s or 10Gb/s Ethernet.) Network traffic in terms of measurement, capacity planning and usage must take into consideration the facts that it is both asymmetric, suffers from variability in bucket size, and is very, very bursty.
…
This complicates things when you consider that at this point scaling out in CPU is easier to do than scaling out in the network. Add virtualization into the mix which drives big, flat, L2 networks as a design architecture layered with a control plane that is now (in the case of Cloud) mostly software driven, provisioned, orchestrated and implemented, and it’s no wonder that folks like Google, Amazon and Facebook are desparate for hugely dense, multi-terabit, wire speed L2 switching fabrics and could use 40 and 100Gb/s Ethernet today…
virtualization.info Newest articles
December 20th, 2011
Oracle has released version 4.1.8 of its virtualization platform VM VirtualBox. This version which can be considered a maintenance release can be installed on top of any VM VirtualBox 4.1.x…
December 20th, 2011
VKernel, recently acquired by Quest Software has released version 4.5. of its vOperations Suite (vOps). vOperations is a suite of products providing Performance Analysis, Capacity Management, Resource Optimization, Reporting and…
December 7th, 2011
Teradici is the developer of the PC-over-IP (PCoIP) remote desktop protocol, which is leveraged in software (by VMware view) and provided with Teradici hardware solutions which are OEM’ed by several…
December 7th, 2011
Citrix has released a whitepaper titled:"Windows 2008 R2 Optimization Guide For Desktop Virtualization with XenApp 6 / 6.5", the paper which contains 23 pages outlines optimization for XenApp 6 and…
December 6th, 2011
In November Microsoft released a public beta of the Microsoft Assessment and Planning Toolkit (MAP) version 6.5. Today Microsoft announced its release, which is the follow-up of version 6.0 which…
December 6th, 2011
Open source vendor Red Hat has released version 6.2 of its Linux distribution, Red Hat Enterprise Linux. This version is the follow-up of version 6.1 which was released in May…
December 6th, 2011
Microsoft has released version 3.2 of the Linux Integration Services for its hypervisor Hyper-V. This version is the follow-up of version 3.1 which was released in July this year.
The…
November 29th, 2011
Since its first official release beginning 2009, the Virtual Session Indexer(VSI) has gained popularity as an independent benchmarking tool. One of the projects using the VSI tool is Project Virtual…
November 21st, 2011
VMware has released version 4.1 of its desktop virtualization platform for Apple Mac: Fusion. This release is considered an minor upgrade for version 4.0 which was released in September this…
November 21st, 2011
In September VMware released a new major version of its virtualization platform Workstation 8.0 and in October it released Player 4.0. Now VMware released an update for its virtualization platform…
November 17th, 2011
VMware has released version 4.7 of of its application virtualization solution ThinApp. This version includes the ability to use ThinApp packages in combination with its Software as a Service (SaaS)…
November 17th, 2011
VKernel, provider of performance and capacity management products, has announced its acquisition by Quest Software. VKernel will operate as a independent subsidiary of Quest.
VKernel entered the virtualization market in…
November 16th, 2011
Lanamark has released a new version of its Capacity Planning platform Suite, this version is the follow up of version 2010 which was released in March last year.
Suite 2012…
November 15th, 2011
In November last year, started releasing Solaris 11 Express, the development version eventually leading to the release of Oracle Solaris 11 which was released last week. Solaris is one of…
Copyright © 2003-2012 virtualization.info. All rights reserved.
virtualization.info | cloudcomputing.info | virtualization.tv | Virtualization Congress