Welcome!

Silverlight Authors: Steven Mandel, Gerardo A Dada, Srinivasan Sundara Rajan, Yeshim Deniz, Greg O'Connor

Related Topics: Microsoft Cloud, Open Source Cloud, IoT User Interface, Silverlight, Release Management , CRM

Microsoft Cloud: 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 PicsArt, Inc.,

@ThingsExpo Stories
Internet-of-Things discussions can end up either going down the consumer gadget rabbit hole or focused on the sort of data logging that industrial manufacturers have been doing forever. However, in fact, companies today are already using IoT data both to optimize their operational technology and to improve the experience of customer interactions in novel ways. In his session at @ThingsExpo, Gordon Haff, Red Hat Technology Evangelist, will share examples from a wide range of industries – includin...
"We build IoT infrastructure products - when you have to integrate different devices, different systems and cloud you have to build an application to do that but we eliminate the need to build an application. Our products can integrate any device, any system, any cloud regardless of protocol," explained Peter Jung, Chief Product Officer at Pulzze Systems, in this SYS-CON.tv interview at @ThingsExpo, held November 1-3, 2016, at the Santa Clara Convention Center in Santa Clara, CA.
With major technology companies and startups seriously embracing IoT strategies, now is the perfect time to attend @ThingsExpo 2016 in New York. Learn what is going on, contribute to the discussions, and ensure that your enterprise is as "IoT-Ready" as it can be! Internet of @ThingsExpo, taking place June 6-8, 2017, at the Javits Center in New York City, New York, is co-located with 20th Cloud Expo and will feature technical sessions from a rock star conference faculty and the leading industry p...
"We're a cybersecurity firm that specializes in engineering security solutions both at the software and hardware level. Security cannot be an after-the-fact afterthought, which is what it's become," stated Richard Blech, Chief Executive Officer at Secure Channels, in this SYS-CON.tv interview at @ThingsExpo, held November 1-3, 2016, at the Santa Clara Convention Center in Santa Clara, CA.
According to Forrester Research, every business will become either a digital predator or digital prey by 2020. To avoid demise, organizations must rapidly create new sources of value in their end-to-end customer experiences. True digital predators also must break down information and process silos and extend digital transformation initiatives to empower employees with the digital resources needed to win, serve, and retain customers.
The IoT is changing the way enterprises conduct business. In his session at @ThingsExpo, Eric Hoffman, Vice President at EastBanc Technologies, discussed how businesses can gain an edge over competitors by empowering consumers to take control through IoT. He cited examples such as a Washington, D.C.-based sports club that leveraged IoT and the cloud to develop a comprehensive booking system. He also highlighted how IoT can revitalize and restore outdated business models, making them profitable ...
In his general session at 19th Cloud Expo, Manish Dixit, VP of Product and Engineering at Dice, discussed how Dice leverages data insights and tools to help both tech professionals and recruiters better understand how skills relate to each other and which skills are in high demand using interactive visualizations and salary indicator tools to maximize earning potential. Manish Dixit is VP of Product and Engineering at Dice. As the leader of the Product, Engineering and Data Sciences team at D...
"Once customers get a year into their IoT deployments, they start to realize that they may have been shortsighted in the ways they built out their deployment and the key thing I see a lot of people looking at is - how can I take equipment data, pull it back in an IoT solution and show it in a dashboard," stated Dave McCarthy, Director of Products at Bsquare Corporation, in this SYS-CON.tv interview at @ThingsExpo, held November 1-3, 2016, at the Santa Clara Convention Center in Santa Clara, CA.
The Internet of Things will challenge the status quo of how IT and development organizations operate. Or will it? Certainly the fog layer of IoT requires special insights about data ontology, security and transactional integrity. But the developmental challenges are the same: People, Process and Platform and how we integrate our thinking to solve complicated problems. In his session at 19th Cloud Expo, Craig Sproule, CEO of Metavine, demonstrated how to move beyond today's coding paradigm and sh...
Today we can collect lots and lots of performance data. We build beautiful dashboards and even have fancy query languages to access and transform the data. Still performance data is a secret language only a couple of people understand. The more business becomes digital the more stakeholders are interested in this data including how it relates to business. Some of these people have never used a monitoring tool before. They have a question on their mind like “How is my application doing” but no id...
@GonzalezCarmen has been ranked the Number One Influencer and @ThingsExpo has been named the Number One Brand in the “M2M 2016: Top 100 Influencers and Brands” by Onalytica. Onalytica analyzed tweets over the last 6 months mentioning the keywords M2M OR “Machine to Machine.” They then identified the top 100 most influential brands and individuals leading the discussion on Twitter.
DevOps is being widely accepted (if not fully adopted) as essential in enterprise IT. But as Enterprise DevOps gains maturity, expands scope, and increases velocity, the need for data-driven decisions across teams becomes more acute. DevOps teams in any modern business must wrangle the ‘digital exhaust’ from the delivery toolchain, "pervasive" and "cognitive" computing, APIs and services, mobile devices and applications, the Internet of Things, and now even blockchain. In this power panel at @...
IoT is rapidly changing the way enterprises are using data to improve business decision-making. In order to derive business value, organizations must unlock insights from the data gathered and then act on these. In their session at @ThingsExpo, Eric Hoffman, Vice President at EastBanc Technologies, and Peter Shashkin, Head of Development Department at EastBanc Technologies, discussed how one organization leveraged IoT, cloud technology and data analysis to improve customer experiences and effici...
As data explodes in quantity, importance and from new sources, the need for managing and protecting data residing across physical, virtual, and cloud environments grow with it. Managing data includes protecting it, indexing and classifying it for true, long-term management, compliance and E-Discovery. Commvault can ensure this with a single pane of glass solution – whether in a private cloud, a Service Provider delivered public cloud or a hybrid cloud environment – across the heterogeneous enter...
Data is the fuel that drives the machine learning algorithmic engines and ultimately provides the business value. In his session at Cloud Expo, Ed Featherston, a director and senior enterprise architect at Collaborative Consulting, discussed the key considerations around quality, volume, timeliness, and pedigree that must be dealt with in order to properly fuel that engine.
Successful digital transformation requires new organizational competencies and capabilities. Research tells us that the biggest impediment to successful transformation is human; consequently, the biggest enabler is a properly skilled and empowered workforce. In the digital age, new individual and collective competencies are required. In his session at 19th Cloud Expo, Bob Newhouse, CEO and founder of Agilitiv, drew together recent research and lessons learned from emerging and established compa...
"IoT is going to be a huge industry with a lot of value for end users, for industries, for consumers, for manufacturers. How can we use cloud to effectively manage IoT applications," stated Ian Khan, Innovation & Marketing Manager at Solgeniakhela, in this SYS-CON.tv interview at @ThingsExpo, held November 3-5, 2015, at the Santa Clara Convention Center in Santa Clara, CA.
Whether your IoT service is connecting cars, homes, appliances, wearable, cameras or other devices, one question hangs in the balance – how do you actually make money from this service? The ability to turn your IoT service into profit requires the ability to create a monetization strategy that is flexible, scalable and working for you in real-time. It must be a transparent, smoothly implemented strategy that all stakeholders – from customers to the board – will be able to understand and comprehe...
Everyone knows that truly innovative companies learn as they go along, pushing boundaries in response to market changes and demands. What's more of a mystery is how to balance innovation on a fresh platform built from scratch with the legacy tech stack, product suite and customers that continue to serve as the business' foundation. In his General Session at 19th Cloud Expo, Michael Chambliss, Head of Engineering at ReadyTalk, discussed why and how ReadyTalk diverted from healthy revenue and mor...
Extracting business value from Internet of Things (IoT) data doesn’t happen overnight. There are several requirements that must be satisfied, including IoT device enablement, data analysis, real-time detection of complex events and automated orchestration of actions. Unfortunately, too many companies fall short in achieving their business goals by implementing incomplete solutions or not focusing on tangible use cases. In his general session at @ThingsExpo, Dave McCarthy, Director of Products...