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What to do when Windows RDS is running slow

What to do when Windows RDS is running slow

That’s the 5th call this week you’ve received about things

feeling “clunky” when an employee is working from home. What

gives? This far into the 21st century you’d think we figured out

how to make a seamless remote desktop experience.

While Microsoft’s Remote Desktop Protocol (RDP) has seen a

lot of upgrades over the years, it’s still not perfect. RDP has

seen its bandwidth footprint reduced considerably and enabled

multimedia support, but there are a number of issues that can

still slow things down. We created this guide to help you

diagnose the problems that can create lag-time for your users

and help you tune your system to work better.

So what are the common culprits that slow down your remote

applications and RDP sessions?

Culprit #1 Bandwidth

Culprit #2 Latency

Culprit #3 Your Server Resources Aren’t Enough

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Bandwidth Latency Server Resources

Culprit #1: BandwidthDespite the improvements in RDP’s overall footprint, a lack of

bandwidth is most often the culprit. Even with the modern

editions of RDP, you should be planning for roughly 100

Kbps/concurrent user for normal office applications and work.

To diagnose if bandwidth is your issue, use a network monitoring

software at your main location to see if it’s hitting its bandwidth

maximum at certain points during the day. If the main location

isn’t an issue, repeat this process for any branch office that’s

having trouble.

Some of your remote users may be connecting from home or

public networks that you can’t control. If the people complaining

are using an unknown variety of networks, bandwidth

constriction at their location is most likely the problem.

What to do?

If you’ve identified that you’re experiencing a bandwidth

problem, there are a few routes that you can take to resolve the

problem.

RDSH Tuning

The most immediate way that you can impact bandwidth

consumption from your remote applications and remote

desktops is by making some changes to the “client experience

settings” within your Remote Desktop Session Host. Microsoft

has a number of suggestions for tuning your Remote Desktop

Session Host. A few of our Favorites from this tuning article are:

>> Disable wallpaper

>> Enable bitmap cache

>> Disable Show contents of windows while dragging

>> Disable Menu and window animation

>> Allow Font smoothing

Individual users logging into a remote desktop session can also

cut bandwidth consumption by lowering the resolution of their

session before starting. This can be found by showing the

“options” prior to connecting and clicking on the “display” tab.

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VoIP

RDR

Email

Data transfer

Videostreaming

Culprit #1: BandwidthUpgrade Your Bandwidth

Sometimes the simplest conclusion is the best. It’s often the

most expensive to do, so if you choose this route make certain

that your issue is raw bandwidth. As discussed at the beginning,

be sure to budget 100 Kbps for your average office user and

higher numbers for more graphically intensive work. Once you’ve

got a handle on where your “peak” bandwidth sits, add more to

account for expected growth before purchasing a bandwidth

upgrade.

If your ISP is unable to provide the bandwidth you need you may

want to look into adding a second line and bonding it with a

product like Peplink or Viprinet. As an added benefit, you can hit

your bandwidth needs and add extra resilience to your network.

That way, if one ISP has a service outage, your network won’t be

lost completely.

WAN Optimization

Wide Area Network (WAN) Optimization is a strong complement

or alternative to upgrading your bandwidth. WAN Optimization

helps you get more out of you existing network by reducing the

amount of data you need to send over the WAN and improving

the way data is transmitted. It will typically require that you have

either a physical device (just behind your firewall) or a virtual

machine at each location that you need to speed up.

The way that WAN Optimization helps out is by drastically

reducing regular traffic across your existing network, freeing up

more bandwidth for RDP sessions. In the case of Sangfor’s WAN

Optimization Controllers, we also optimize the TCP/IP and UDP

protocols that RDP uses to communicate. This means that not

only will you have more room for remote applications and

remote desktop sessions, but also that those sessions will

perform better.

For more detail into how to diagnose a bandwidth problem and

your options for solving it, check out our article on

troubleshooting RDS bandwidth issues.

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Culprit #2 LatencyLatency is the second most common cause of complaints for

remote applications and desktop sessions. People tend to notice

the impact of latency when it reaches 50ms or above, so as a

best practice you want to make sure that RDP sessions are

hosted within 1500 miles of a user. Why 1500 miles? Because

under perfect conditions (a direct fiber cable) a round trip for a

packet would be ~25ms.

Speed of light in a fiber optic cable = 128,534 miles per second

Round trip length for packet / acknowledgement = 3,000 miles

3,000 miles / 128,534 mps = .0233 seconds.

Under real conditions, it’s best to add about 30ms to account for

congestion and lag times at routing points in between. So

beyond 1500 miles you would expect users to feel some lag time

even if you’ve done everything in your power to improve their

experience. This is one reason why Amazon and Microsoft Azure

have server farms located all over the world.

Latency is fairly easy to diagnose. Log into a device or virtual

machine on the same LAN where your RDS servers are hosted

and use command prompt ping one of the locations or devices

that is experiencing an issue. If the problem is at your location,

simply ping the ip address of the HQ or datacenter that you

access for RDP sessions.

If you find that the latency is regularly going above 50ms, it is

likely impacting your user’s RDS experience. To get a better idea

on where things are slowing down, you can use traceroute to

check each routing point.

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Culprit #2 LatencyWhat to do?

While easy to diagnose, latency can be a little tricky to fix – since

often you are limited by the speed of light and the routing speed

from central providers you have no control over. However, there

are a few ways to cut down on latency.

Colocation

As noted above, the first thing to do is make sure that your

connection speed is not limited by the laws of physics – if you’ve

got people consistently connecting from over 1500 miles away,

they are going to have a little latency. That means the best

defense against latency is having a closer location host the

applications that your team is accessing.

Many people resolve this issue by colocating at a nearby

datacenter and replicating important shared data to their official

HQ or datacenter. Most datacenters today have ample security

measures in place to be commensurate with a privately run DC

and have enough bandwidth that data fetching and replication is

much faster than it would be from a local office.

WAN Optimization

More than just reducing bandwidth consumption, a number of

WAN Optimization tools also improve upon existing protocols to

reduce the impact of latency on user experience. Sangfor’s WAN

Optimization Controllers do this by taking the best elements of

both TCP and UDP, tuning the way our protocol handles

congestion, and a few other proprietary tweaks to the base

protocols. The end result is our Highspeed Transfer Protocol

(HTP), which can deliver data at higher speeds while still

accounting for issues like packet loss.

While bandwidth keeps becoming more available and less

expensive, latency continues to create problems for companies

around the world. Many Fortune 500 companies who have plenty

of bandwidth still rely on WAN Optimization devices exclusively

to reduce the impact of latency.

For more detail into how to diagnose a latency problem and your

options for solving it, check out our article on troubleshooting

RDS latency issues.

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WAN

Culprit #3 Your Server Resources Aren’t EnoughSometimes the problem is simply overloading your available

resources. Often this is an issue of load balancing rather than

maxing out your available hardware. Because Microsoft’s

Network Load Balancing (NLB) software is not automatically

installed with Windows 2012, the hassle of installing it on every

server in a cluster manually is sometimes overlooked, leading to

problems using remote applications or desktop sessions.

The best way to find if you have a resource problem is to install a

monitoring tool to identify if a given server or cluster is taking on

more work than it can handle.

What to do?

Update, Upgrade, or Migrate

If you find that every server in your network is hitting its limit

during peak hours, it may be time for a hardware refresh, adding

more hardware, or moving to a cloud provider where you can

expand and contract resources as your needs do.

Get a resource-based Load Balancer

If you find that one or two servers seem to be overloaded while

the others are fine, you’ve got a load balancing problem. If all

you’re using is the standard NLB software from Microsoft, it’s

important to know that it balances based on client requests

rather than the resources necessary to comply with those

requests. So if one server has 5 requests running MS word, it’s

not very taxed, while another with 5 requests all running

AutoCAD may be at the end of its CPU and GPU capability. To a

standard implementation of NLB, the server load would look

equal even though that’s definitely not the case.

There are numerous options for load balancing, just be sure that

it has resource-based load balancing as a feature. If you’d like to

see the difference immediately, we suggest starting a free trial of

EasyConnect. One of EasyConnect’s standard features is

resource-based load balancing that looks at CPU, I/O, and RAM

usage to determine which server should handle what request.

For more detail into how to diagnose a resource problem and

your options for solving it, check out our article on

troubleshooting RDS resource issues.

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How EasyConnect Can Help

Whether your RDS problem ends up being bandwidth, latency,

or resource utilization, Sangfor’s EasyConnect can quickly

provide dramatic improvement to your user’s experience with

remote applications. Installing a free 30 day trial takes less than

60 minutes and comes with a video walkthrough on how to

install and configure.

EasyConnect is built to address all three of the most common

challenges that impact Windows RDS performance:

Low bandwidth

EasyConnect utilizes Sangfor’s existing WAN Optimization

technologies to dramatically reduce bandwidth consumption for

people accessing resources via EasyConnect. The central

appliance uses byte caching to permanently improve upload

speeds and the EasyConnect client creates a temporary cache

on a user’s machine for improved download speeds.

High Latency and Packet loss

EasyConnect uses the HTP protocol pioneered in our WAN

Optimization Controllers to speed up the underlying TCP and

UDP used in an RDP session. When transmitting to a user device,

EasyConnect also uses the higher-efficiency SRAP (Sangfor

Remote Application Protocol) rather than RDP. By improving the

communication protocols at both the application layer and data

layer we dramatically improve the efficiency of transmitting

remote applications – boosting how quickly applications

respond.

Poor Resource Utilization

As discussed above, EasyConnect gets the most out of your

server, cluster, or cloud through resource-based load balancing

that looks at CPU, I/O, and RAM to determine which server

should handle what request.

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info@sangfor.net Sangfor Technologieswww.sangfor.net

info@sangfor.net 2901 Tasman Dr., Suite 107

Santa Clara CA, 95054

Sangfor Technologieswww.sangfor.net (408) 520-7898

Copyright © 2015 Sangfor Technologies Inc. All Rights Reserved.

Sangfor Technologies

SANGFOR TECHNOLOGIES

Sangfor is a global leader in networking technology that has helped more than 28,000 businesses make

their networks faster, simpler, and safer. Sangfor’s networking solutions allow enterprieses to successfully

run critical applications on any device, anytime, and anywhere. With over 2,000 employees and 55 worldwide

offices. Sangfor has proven their WAN Optimization, EasyConnect, and Next Generation Firewall products in

competitive markets around the world.

Sangfor’s Products

WAN OptimizationLAN Speed on WAN

Sangfor WAN Optimization improves your Internet, WAN, and

cloud speeds through better traffic flow, reduced congestion,

and faster transmission. Branch offices and remote users

enjoy a LAN-like experience with faster application

performance, downloads, and data transfers.

EasyConnect securely delivers applications from a server,

private cloud, or public cloud into the hands of employees. By

utilizing EasyConnect, a business can move their data and

computing resources to a datacenter or server room -

reducing IT costs and allowing employees to choose where

they work and what device they use for access.

Sangfor NGFW is designed to defend attacks end to end, from

layer 2 to layer 7, in multigigabit speed, with the focus on the

application layer. Sangfor NGFW allows organizations to

better defend against increasingly sophisticated network

threats, identifying and blocking the misuse of applications

precisely and effectively.

EasyConnectAny Application Anywhere

Next Gen FirewallProactive Network Security