what to do when windows rds running slow?
TRANSCRIPT
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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
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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