Hear from our product management and engineering teams about three topics that will help you unlock more value from our dynamic languages agents: • Diagnosing a slow business transaction in Node.js • Using the agent APIs to create custom transactions and exit calls • Getting the Java proxy out of your Docker containers and connecting multiple agents to one proxy For more information, go to: www.appdynamics.com

1. Microservices, code profiling, and extensibility
Getting more out of the Node.js, PHP, and Python agents
Dave Roth (Engineering Manager, Node.js & .NET)
Dan Koepke (Engineering Manager, Dynamic Languages)
Viktor Gavrielov (Software Engineer, Dynamic Languages)
Rakesh Patel (Product Manager, Dynamic Languages)

2. APPDYNAMICS CONFIDENTIAL AND PROPRIETARY 2
Notice
The information and materials included in this presentation (collectively, the
“Materials”) are the proprietary information of AppDynamics, Inc. (“AppDynamics” or
the “Company”). No part of the Materials may be reproduced, distributed,
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derivative work, without prior written permission from AppDynamics.
The Materials may contain product roadmap information of AppDynamics.
AppDynamics reserves the right to change any product roadmap information at any
time, for any reason and without notice. This information is intended to outline
AppDynamics' general product direction, it is not a guarantee of future product
features, and it should not be relied on in making a purchasing decision. The
development, release, and timing of any features or functionality described for
AppDynamics' products remains at AppDynamics' sole discretion. AppDynamics
reserves the right to change any planned features at any time before making them
generally available as well as never making them generally available.
All third-party trademarks, including names, logos and brands, referenced by
AppDynamics in this presentation are property of their respective owners. All
references to third-party trademarks are for identification purposes only and shall be
considered nominative fair use under trademark law. © 2016 AppDynamics, Inc. All
rights reserved.

3. Product announcements
Rakesh Patel
Product Manager for Dynamic Languages

4. Using the agent APIs
Viktor Gavrielov
Software Engineer, Dynamic Languages

5. Dynamic Languages Agent APIs: Use Case
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6. Dynamic Languages Agent APIs
Extend and customize various aspects of AppDynamics AIP.
• PHP, Python, and Node.js APIs
• C++ and Golang SDK
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7. Dynamic Languages Agent APIs
AppDynamics Agent APIs let you:
• Start and end custom BTs anywhere and anytime
• Start and end custom Exitcalls anywhere and anytime
• Interact with already discovered Backends
• Add your own Backend
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8. Python Agent API
setup()
while sunIsOut:
do_work()
teardown()
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9. Python Agent API
from appdynamics.agent import api as appd
setup()
while sunIsOut:
bt_handle = appd.start_bt('do work')
try:
do_work()
except Exception as exc:
raise
finally:
appd.end_bt(bt_handle, exc)
teardown()
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10. Python Agent API
setup()
while sunIsOut:
with bt('do work'):
do_work()
teardown()
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11. Dynamic Languages Agent APIs
Extend and customize AppDynamics AIP
• PHP, Python, and Node.js APIs
• C++ and Golang SDK
AppDynamics Confidential and Proprietary 13

12. APPDYNAMICS CONFIDENTIAL AND PROPRIETARY 14
Quick Q&A (1-2 questions)
(Also Q&A at the end)

13. Setting up a multi-tenant
proxy in Docker
Dan Koepke
Engineering Manager, Dynamic Languages

14. Background: Docker
Docker is a tool for easily creating and running containers.
• Containers are lightweight VMs
• Generally single purpose: just my application/service/micro-service
• Simplifies application deployment
– Build container and ship it to the hosts
– Run locally (for dev/test) the same way as in production
• Get the positives of shared hosting without the negatives
– Better resource utilization
– Isolation for security and reliability
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15. Background: Proxy
AppDynamics proxy performs aggregation and reporting for
dynamic language agents.
• Centralizes common agent logic to reduce agent overhead
• Supports multi-process models (e.g., mod_php, Python)
• Multi-tenant for shared hosting
• Currently implemented in Java
• Proxy must run on same host as agent
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16. Dynamic Languages Agent architecture
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Application
AppDynamics Agent AppDynamics Proxy
AppDynamics Controller
IPC
HTTP

17. Containers and AppDynamics
AppDynamics can monitor your containerized applications and
services.
• Bake the agent into the container
• The proxy can also be baked into the container so that it runs inside,
but...
– Need larger containers
– Pay the JVM overhead for each container
• Alternatively, run a single proxy on the host, shared by the containers
– No extra JVM process running in the containers
– No wasted resources
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18. Shared proxy architecture
Docker host
Containerized
Application
AppDynamics Agent
AppDynamics Proxy
AppDynamics Controller
IP
C
Containerized
Application
AppDynamics Agent
IP
C

19. Steps to a shared proxy
Sharing the proxy in four easy steps
• Install the agent(s) on the host
– Need to install the agent for each type of agent used in the containers
– The proxy is specific to each type of agent
• Run the proxy/proxies on the host
• Mount the proxy communication directory as a data volume in your
containers
• Configure the agent to use the volume to communicate to the proxy
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20. Running the proxy
Slightly different for each agent
• Find on the docs site:
o Node.js: http://bit.ly/2eSOcLK
o PHP: http://bit.ly/2eHbGqH
o Python: http://bit.ly/2ewMhj7
• Setup to run automatically when the host starts
• Specify a unique proxy communication directory for each proxy you
run
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21. The proxy host data volume
A data volume is for accessing persistent or shared data across containers
• Specified with the “-v” option to docker create/run
• A host directory can be mapped to a data volume
– Example: “-v /src/foo:/opt/foo”
– Maps host directory “/src/foo” to directory “/opt/foo” within container
• Proxy communication dir is where IPC occurs, passed to proxy on
startup
• For example:
– docker run -d -P --name web -v /tmp/appd:/tmp/appd apps/web supervisor
start web
AppDynamics Confidential and Proprietary 23

22. APPDYNAMICS CONFIDENTIAL AND PROPRIETARY 24
Quick Q&A (1-2 questions)
(Also Q&A at the end)

23. Diagnosing a slow BT in
Node.js
Dave Roth
Engineering Manager For Node.js & .NET

24. Three sources of latency in Node.js applications
• The event loop is executing code that is part of the BT.
– Where to look: the call graph of a BT snapshot.
• Exit calls to other tiers, DBs, etc.
– Where to look: exit calls tab of a BT snapshot.
• Callbacks sitting in the event loop queue once an async operation is
done (DB call or HTTP call to another tier).
– Where to look: process snapshots tab
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25. Example: identifying latency in a Node.js BT
This BT took 111ms
to execute. Let’s
drill down to
account for the
latency...
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26. Latency source #1: work for this BT
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In this case, 30 ms were spent doing work for this BT in the event loop.
(The call graph often doesn’t show any methods or shows 0ms as its execution time. That is normal and
means that the event loop did not much time executing the BT itself.)

27. Latency source #2: exit calls
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The exit call was done async and very quickly (10 ms).

28. Latency source #3: the event loop
When exit calls come back from the downstream tiers or DBs, Node.js
is notified that their responses are ready to be consumed.
Node.js will then schedule the callback function for each of those exit
calls to run in the next iteration of the event loop.
If the event loop is doing something else, for another BT or otherwise,
those callback functions will sit in the queue and not get called.
This is the third source of latency.
AppDynamics Confidential and Proprietary 30

29. Latency source #3: the event loop
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• Process snapshots capture all event
loop activity during the time the
snapshot is taken.
• Accessible from the overview tab of
a BT snapshot.

30. Latency source #3: the event loop
The process snapshot
begins to reveal where
the event loop is
spending its time.
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31. Latency source #3: the event loop
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Drilling down to find the
offending class...

32. Latency source #3: the event loop
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…and finally the
offending line of
code, in this case a
logging library.

33. Other places to look: metric browser
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The most useful metrics to use in most
situations are:
• Event loop metrics – shows timing info that
can point to problems or stuck event loops.
• Garbage Collection – GC in Node.js pauses
the process so it’s something important to
keep track of.
• Memory – heap metrics show utilization of
the memory by all the objects in the runtime.

34. Using the metric browser to diagnose event loop issues
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• Average IO time – average time spent running
callbacks. Spikes mean the callbacks are
heavy.
• Avg and Max Tick length – how long is the
event loop tacking to go through an iteration. If
tick length spikes and IO time (above) stays
constant, something else is monopolizing the
event loop
• Tick count is a similar metric as it will show how
many times the event loop iterated over a 1-
minute period.

35. For further reference...
1.Come find us at the booths
2.AppDynamics documentation
3.File a support ticket
AppDynamics Confidential and Proprietary 37

36. Q & A

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38. Thank you