Click here to close now.

Welcome!

AJAX & REA Authors: Michael Jannery, XebiaLabs Blog, Plutora Blog, Carmen Gonzalez, David Sprott

Related Topics: .NET, Open Source, AJAX & REA, Silverlight, Open Web, CRM

.NET: Blog Feed Post

Performance Tuning Windows 2012: Network Subsystem | Part 1

NDIS, the protocol stack, and user mode applications

Offload Capabilities
Offloading tasks can reduce CPU usage on the server, which improves the overall system performance. The network stack in Windows 2012 (and prior versions of the OS) can offload one or more tasks to a network adapter permitted you have an adapter with offload capabilities. The table below lists the details about offload capabilities:

Receive-side scaling (RSS) is a network driver technology that enables the efficient distribution of network receive processing across multiple CPUs in multiprocessor systems.

Checksum calculation

The network stack can offload the calculation and validation of Transmission Control Protocol (TCP) and User Datagram Protocol (UDP) checksums on send and receive code paths. It can also offload the calculation and validation of IPv4 and IPv6 checksums on send and receive code paths.

IP security authentication and encryption

The TCP/IP transport layer can offload the calculation and validation of encrypted checksums for authentication headers and Encapsulating Security Payloads (ESPs). The TCP/IP transport layer can also offload the encryption and decryption of ESPs.

Segmentation of large TCP packets

The TCP/IP transport layer supports Large Send Offload v2 (LSOv2). With LSOv2, the TCP/IP transport layer can offload the segmentation of large TCP packets to the hardware.

Receive Segment Coalescing (RSC)

RSC is the ability to group packets together to minimize the header processing that is necessary for the host to perform. A maximum of 64 KB of received payload can be coalesced into a single larger packet for processing.

Receive-Side Scaling (RSS)

Receive-Side Scaling (RSS)
Windows Server 2012 (as well as Windows Server 2008 R2, and Windows Server 2008) supports Receive Side Scaling (RSS). RSS directs network processing to up to one logical processor per core. For example, given a server with Intel Hyper-Threading and 4 cores (8 logical processors), RSS will use no more than 4 logical processors for network processing.
RSS distributes incoming network I/O packets among logical processors so that packets that belong to the same TCP connection are processed on the same logical processor. RSS also load balances UDP unicast and multicast traffic from Windows Server 2012, and it routes related flows (as determined by hashing the source and destination addresses) to the same logical processor, preserving the order of related arrivals. Windows Server 2012 provides the following methods to tune RSS behavior:

· Windows PowerShell: Get-NetAdapterRSS, Set-NetAdapterRSS, Enable-NetAdapterRss, Disable-NetAdapterRss. These cmdlets allow you to view and modify RSS parameters.

· RSS Profiles: Used to determine which logical processors are assigned to which network adapter. Possible profiles are:

o Closest. Logical processor numbers near the network adapter’s base RSS processor are preferred. Windows may rebalance logical processors dynamically based on load.

o ClosestStatic. Logical processor numbers near the network adapter’s base RSS processor are preferred. Windows will not rebalance logical processors dynamically based on load.

o NUMA. Logical processor numbers will tend to be selected on different NUMA nodes to distribute the load. Windows may rebalance logical processors dynamically based on load.

o NUMAStatic. This is the default profile. Logical processor numbers will tend to be selected on different NUMA nodes to distribute the load. Windows will not rebalance logical processors dynamically based on load.

o Conservative: RSS uses as few processors as possible to sustain the load. This option helps reduce the number of interrupts.

You can use the set-netadapterRSS cmdlet to choose how many logical processors can be used for RSS on a per-network adapter basis, the starting offset for the range of logical processors, and which node the network adapter allocates memory from:

· MaxProcessors: Sets the maximum number of RSS processors to be used, ensuring application traffic is bound to a maximum number of processors on an interface.

set-netadapterRSS –Name “Ethernet” –MaxProcessors <value>

· BaseProcessorGroup: Sets the base processor group of a NUMA node, affecting the processor array used by RSS.

set-netadapterRSS –Name “Ethernet” –BaseProcessorGroup <value>

· MaxProcessorGroup: Sets the Max processor group of a NUMA node, affecting the processor array used by RSS.

set-netadapterRSS –Name “Ethernet” –MaxProcessorGroup <value>

· BaseProcessorNumber: Sets the base processor number of a NUMA node, allowing partitioning processors across network adapters and specifying the first logical processor in the range of RSS processors that is assigned to each adapter.

set-netadapterRSS –Name “Ethernet” –BaseProcessorNumber <Byte Value>

· NumaNode: The NUMA node that each network adapter can allocate memory from.

set-netadapterRSS –Name “Ethernet” –NumaNodeID <value>

· NumberofReceiveQueues: If your logical processors seem to be underutilized for receive traffic, you can try increasing the number of RSS queues from the default of 2 to the maximum number supported.

set-netadapterRSS –Name “Ethernet” –NumberOfReceiveQueues <value>

RSS does not provide any interaction with virtual machines, instead you can configure VMQ. RSS can be enabled for virtual machines in the case of SR-IOV because the virtual function driver supports RSS capability. In this case, the guest and the host will have the benefit of RSS. The host however, does not get RSS capability because the virtual switch is enabled with SR-IOV.

Receive-Segment Coalescing (RSC)
Receive Segment Coalescing can improve performance by reducing the number of IP headers that are processed for a given amount of received data.  You should use RSC to tune performance of received data by grouping (or coalescing) smaller packets into larger units. This can reduce latency and increase throughput for received heavy workloads. On network adapters supporting RSC, make sure that it is enabled, unless you have low latency, low throughput networking needs that benefit from RSC being turned off.

In Windows Server 2012 you can use the following PowerShell cmdlets to configure RSC capable adapters: Enable-NetAdapterRsc, Disable-NetRsc, Get-NetAdapterAdvancedProperty, and Set-NetAdapterAdvancedProperty. RSC can be examined using the cmdlets Get-NetAdapterRSC and Get-NetAdapterStatistics. The Get cmdlet shows if RSC is enabled and if TCP enables RSC to be in operational state. In the example above, IPv4 RSC is enabled. To understand failures, you can view the coalesced bytes or exceptions caused by entering the following command:

PS C:\Users\Administrator> $x = Get-NetAdapterStatistics “myAdapter”

PS C:\Users\Administrator> $x.rscstatistics

CoalescedBytes : 0

CoalescedPackets : 0

CoalescingEvents : 0

CoalescingExceptions : 0

RSC and virtualization
If the host adapter is not bound to the virtual switch, RSC is supported on the physical host. If the adapter is bound to the virtual switch, Windows 2012 will disable RSC on the physical host.
RSC can be enabled for a virtual machine when SR-IOV is enabled. In this case, virtual functions will support RSC capability; hence, virtual machines will also get the benefit of RSC.

Network Adapter Resources

A few network adapters actively manage their resources to achieve optimum performance. Several network adapters let the administrator manually configure resources by using the Advanced Networking tab for the adapter. For such adapters, you can set the values of a number of parameters including the number of receive buffers and send buffers.  In Windows Server 2012, you can configure advanced network settings using the following PowerShell cmdlets:

  • Get-NetAdapterAdvancedProperty
  • SetNetAdapterAdvancedProperty
  • Enable-NetAdapter
  • Enable-NetAdapterBinding
  • Enable-NetAdapterChecksumOffload
  • Enable-NetAdapterLso
  • Enable-NetAdapterIPSecOffload
  • Enable-NetAdapterPowerManagemetn
  • Enable-NetAdapterQos
  • Enable-NetAdapterRDMA
  • Enable-NetAdapter
  • Enable-NetAdapterSriov

Message-Signaled Interrupts (MSI/MSI-X)
Network adapters that support MSI/MSI-X can target specific logical processors. If your network adapter also support RSS, then a logical processor can be dedicated to servicing interrupts and deferred procedure calls (DPCs) for a given TCP connection. This will greatly improve performance, by preserving the TCP cache.

Interrupt Moderation
Lastly, we’ll discuss interrupt moderation. Some network adapters expose different interrupt moderation levels, or buffer coalescing parameters, or both. You definitely should consider buffer coalescing when the network adapter does not perform interrupt moderation. Interrupt moderation will reduce CPU utilization because it minimizes the per-buffer processing cost, but you should consider that interrupt-moderation  and buffer coalescing can have a negative impact on latency-sensitive situations. The table below lists the suggested adapter features for various server roles.

Role

Checksum offload

Large Send Offload (LSO)

Receive-side scaling (RSS)

Receive Segment Coalescing (RSC)

File server

X

X

X

X

Web server

X

X

X

Mail server (short-lived connections)

X

X

Database server

X

X

X

FTP server

X

X

X

Media server

X

X

X

These settings serve as guidelines only . Depending on the workload, your network adapter(s), and your specific situation, your experience can be different. In our next article we’ll go deeper into tuning the network adapter and utilizing some of the features we discussed.

Read the original blog entry...

More Stories By Hovhannes Avoyan

Hovhannes Avoyan is the CEO of Monitis, Inc., a provider of on-demand systems management and monitoring software to 50,000 users spanning small businesses and Fortune 500 companies.

Prior to Monitis, he served as General Manager and Director of Development at prominent web portal Lycos Europe, where he grew the Lycos Armenia group from 30 people to over 200, making it the company's largest development center. Prior to Lycos, Avoyan was VP of Technology at Brience, Inc. (based in San Francisco and acquired by Syniverse), which delivered mobile internet content solutions to companies like Cisco, Ingram Micro, Washington Mutual, Wyndham Hotels , T-Mobile , and CNN. Prior to that, he served as the founder and CEO of CEDIT ltd., which was acquired by Brience. A 24 year veteran of the software industry, he also runs Sourcio cjsc, an IT consulting company and startup incubator specializing in web 2.0 products and open-source technologies.

Hovhannes is a senior lecturer at the American Univeristy of Armenia and has been a visiting lecturer at San Francisco State University. He is a graduate of Bertelsmann University.

@CloudExpo Stories
SYS-CON Media announced today that Symantec, a provider of leading security, backup and availability solutions for where vital information is stored, accessed and shared, has launched new ad campaigns on SYS-CON's i-Technology sites, which include Cloud Computing Journal, DevOps Journal, Virtualization Journal, and IoT Journal. Symantec’s campaigns focus on Disaster Recovery and High Availability, the availability of business-critical applications in today’s complex heterogeneous environments, ...
We certainly live in interesting technological times. And no more interesting than the current competing IoT standards for connectivity. Various standards bodies, approaches, and ecosystems are vying for mindshare and positioning for a competitive edge. It is clear that when the dust settles, we will have new protocols, evolved protocols, that will change the way we interact with devices and infrastructure. We will also have evolved web protocols, like HTTP/2, that will be changing the very core...
Skytap Inc., has appointed David Frost as vice president of professional services. David joins Skytap from Deloitte Consulting where he served as Managing Director leading SAP, Cloud, and Advanced Technology Services. At Skytap, David will head the company's professional services organization, and spearhead a new consulting practice that will guide IT organizations through the adoption of DevOps best practices. David's appointment comes on the heels of Skytap's recent $35 million Series D fundin...
Operational Hadoop and the Lambda Architecture for Streaming Data Apache Hadoop is emerging as a distributed platform for handling large and fast incoming streams of data. Predictive maintenance, supply chain optimization, and Internet-of-Things analysis are examples where Hadoop provides the scalable storage, processing, and analytics platform to gain meaningful insights from granular data that is typically only valuable from a large-scale, aggregate view. One architecture useful for capturing...
Today’s enterprise is being driven by disruptive competitive and human capital requirements to provide enterprise application access through not only desktops, but also mobile devices. To retrofit existing programs across all these devices using traditional programming methods is very costly and time consuming – often prohibitively so. In his session at @ThingsExpo, Jesse Shiah, CEO, President, and Co-Founder of AgilePoint Inc., discussed how you can create applications that run on all mobile ...
SYS-CON Events announced today that Vitria Technology, Inc. will exhibit at SYS-CON’s @ThingsExpo, which will take place on June 9-11, 2015, at the Javits Center in New York City, NY. Vitria will showcase the company’s new IoT Analytics Platform through live demonstrations at booth #330. Vitria’s IoT Analytics Platform, fully integrated and powered by an operational intelligence engine, enables customers to rapidly build and operationalize advanced analytics to deliver timely business outcomes ...
DevOps is about increasing efficiency, but nothing is more inefficient than building the same application twice. However, this is a routine occurrence with enterprise applications that need both a rich desktop web interface and strong mobile support. With recent technological advances from Isomorphic Software and others, it is now feasible to create a rich desktop and tuned mobile experience with a single codebase, without compromising performance or usability.
The speed of software changes in growing and large scale rapid-paced DevOps environments presents a challenge for continuous testing. Many organizations struggle to get this right. Practices that work for small scale continuous testing may not be sufficient as the requirements grow. In his session at DevOps Summit, Marc Hornbeek, Sr. Solutions Architect of DevOps continuous test solutions at Spirent Communications, will explain the best practices of continuous testing at high scale, which is r...
Docker has acquired software-defined networking (SDN) startup SocketPlane. SocketPlane, which was founded in Q4, 2014, with a vision of delivering Docker-native networking, has been an active participant in shaping the initial efforts around Docker’s open API for networking. The explicit focus of the SocketPlane team within Docker will be on collaborating with the partner community to complete a rich set of networking APIs that addresses the needs of application developers and network and system...
Containers and microservices have become topics of intense interest throughout the cloud developer and enterprise IT communities. Accordingly, attendees at the upcoming 16th Cloud Expo at the Javits Center in New York June 9-11 will find fresh new content in a new track called PaaS | Containers & Microservices Containers are not being considered for the first time by the cloud community, but a current era of re-consideration has pushed them to the top of the cloud agenda. With the launch ...
SYS-CON Events announced today that Dyn, the worldwide leader in Internet Performance, will exhibit at SYS-CON's 16th International Cloud Expo®, which will take place on June 9-11, 2015, at the Javits Center in New York City, NY. Dyn is a cloud-based Internet Performance company. Dyn helps companies monitor, control, and optimize online infrastructure for an exceptional end-user experience. Through a world-class network and unrivaled, objective intelligence into Internet conditions, Dyn ensures...
In their session at @ThingsExpo, Shyam Varan Nath, Principal Architect at GE, and Ibrahim Gokcen, who leads GE's advanced IoT analytics, focused on the Internet of Things / Industrial Internet and how to make it operational for business end-users. Learn about the challenges posed by machine and sensor data and how to marry it with enterprise data. They also discussed the tips and tricks to provide the Industrial Internet as an end-user consumable service using Big Data Analytics and Industrial C...
JFrog on Thursday announced that it has added Docker support to Bintray, its distribution-as-a-service (DaaS) platform. When combined with JFrog’s Artifactory binary repository management system, organizations can now manage Docker images with an end-to-end solution that supports all technologies. The new version of Bintray allows organizations to create an unlimited number of private Docker repositories, and through the use of fast Akamai content delivery networks (CDNs), it decreases the dow...
Performance is the intersection of power, agility, control, and choice. If you value performance, and more specifically consistent performance, you need to look beyond simple virtualized compute. Many factors need to be considered to create a truly performant environment. In his General Session at 15th Cloud Expo, Harold Hannon, Sr. Software Architect at SoftLayer, discussed how to take advantage of a multitude of compute options and platform features to make cloud the cornerstone of your onlin...
The explosion of connected devices / sensors is creating an ever-expanding set of new and valuable data. In parallel the emerging capability of Big Data technologies to store, access, analyze, and react to this data is producing changes in business models under the umbrella of the Internet of Things (IoT). In particular within the Insurance industry, IoT appears positioned to enable deep changes by altering relationships between insurers, distributors, and the insured. In his session at @Things...
Platform-as-a-Service (PaaS) is a technology designed to make DevOps easier and allow developers to focus on application development. The PaaS takes care of provisioning, scaling, HA, and other cloud management aspects. Apache Stratos is a PaaS codebase developed in Apache and designed to create a highly productive developer environment while also supporting powerful deployment options. Integration with the Docker platform, CoreOS Linux distribution, and Kubernetes container management system ...
Even as cloud and managed services grow increasingly central to business strategy and performance, challenges remain. The biggest sticking point for companies seeking to capitalize on the cloud is data security. Keeping data safe is an issue in any computing environment, and it has been a focus since the earliest days of the cloud revolution. Understandably so: a lot can go wrong when you allow valuable information to live outside the firewall. Recent revelations about government snooping, along...
SYS-CON Media announced that IBM, which offers the world’s deepest portfolio of technologies and expertise that are transforming the future of work, has launched ad campaigns on SYS-CON’s numerous online magazines such as Cloud Computing Journal, Virtualization Journal, SOA World Magazine, and IoT Journal. IBM’s campaigns focus on vendors in the technology marketplace, the future of testing, Big Data and analytics, and mobile platforms.
It’s been proven time and time again that in tech, diversity drives greater innovation, better team productivity and greater profits and market share. So what can we do in our DevOps teams to embrace diversity and help transform the culture of development and operations into a true “DevOps” team? In her session at DevOps Summit, Stefana Muller, Director, Product Management – Continuous Delivery at CA Technologies, will answer that question citing examples, showing how to create opportunities f...
IBM has announced that SoftLayer will offer OpenPOWER-based servers as part of its portfolio of cloud-based services. With the new offering, clients will be able to select OpenPOWER-based “bare metal” servers when configuring their cloud-based IT infrastructure from SoftLayer, an IBM company. Leveraging the OpenPOWER Foundation design concept, the servers were developed to help clients better manage data-intensive workloads on public and private clouds. Increasingly cloud technologies, bot...