Little Networks

Stacy Devino Dallas Android Developers

Jan. 2016

STACY DEVINO

•Senior Android Innovator at The Home

Depot Dallas Technology Center

•Works on Consumer Mobile App and

Internal Product Innovation

•WTM Lead DFW, SixSigma BlackBelt,

Intel Innovator, DMS Member, Vintage

game collector/restorer

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WEBSITES www.stacydevino.com www.ledgoes.com www.openbrite.com

EMAIL childofthehorn@gmail.com

G+ https://plus.google.com/+StacyDevino

TWITTER @DoesitPew

Biggest Issues

● Large, Unfiltered Images

● Untracked Data Usage (Does that API really need to be active right now? )

● Non-optimized Network handling (Batching)

● Not Using the Android tools to help you

● Bad API designs

● Doubled / Badly Handled API calls

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Tracking Your Application DataUsing the Android Tools

Network Monitor in Android Studio

TrafficStats API in Android (http://goo.gl/9cu59J)

Watching your APIs and responses

Charles Proxy (not free, but worth the money)

Detailed Tracking of Network Data (with Forensics)

Application Resource Optimizer (ARO) by ATT (easiest)

Wireshark

Shark for Root (locally on the device)4

Capturing a PCAPPCAP files are used to track network communications and data

Rooted Phones (see http://goo.gl/uMFv2N for non-rooted phones)

1. Grab a copy of tcpdump from http://goo.gl/YbyaA2

2. Go to Settings > Apps > Running Apps and Force Stop any services that are not part of the Android System (or use Development options > Background process limit > At most 2 processes )

3. Now open just the app you want to test

4. Open a Terminal and type “adb push tcpdump /sdcard”, "adb shell", "su", “cp /sdcard/tcpdump /system/xbin”, and then “chmod 755 tcpdump”

If using Wifi:

1. "tcpdump -i wlan0 -s 65535 -w /sdcard/networktrace.pcap"

If using Cellular (rmnetusb0 is also possible, look at “ip addr”): 1. "tcpdump -i rmnet0 -s 65535 -w /sdcard/networktrace.pcap"

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Download + InstalL ARO

1.Download the appropriate version for your OS and Mobile Platform here : https://goo.gl/gTIvwt

2.Download the DiffTool utility for doing side by side comparisons of before and after a change https://goo.gl/f1ai6M

3.Source for ARO : https://github.com/attdevsupport/ARO

4.Install Dependencies : WinPCAP and JRE 6.0+

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ARO Main Summary▪ Quick, Valuable

insight to major issues which may be occurring.

▪ Track Image sizes and downloaded resources

▪ Cached Resources

▪ Duplicated APIs

▪ Areas of Improvement

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ARO Main Summary (Competitor)

You can track your app’s performance just as well as you can track your competitor. It can be a great way to see how your app performance in that market compares as well as be able to find valuable insight to things they may be doing right where you are not.

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ARO Main Summary (Competitor)▪ Gives you the reasons

for your failures

▪ No cache headers?

▪ That could be a problem for reused web resources, making the device re-download (using more data).

▪ Cache is King! $$$$$

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ARO Main Summary (Competitor)

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ARO Profiles▪ Define your own WIN

parameters

▪ Allows you to track your performance against your user defined values.

▪ Very useful if you have made new Cellular performance characteristics to your APIs and need to verify it is within the desired performance (and getting correct values!)

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ARO Overview

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ARO Diagnostics ( i.e.Network Monitor )

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ARO Stats

Overall Score Sheet

How did Yah do?

Eh, not bad

But, we can DO BETTER!

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▪ Compression is your FRIEND

▪ PNG vs JPEG vs WebP

▪ 85% Quality JPEG with Smoothing can reduce a 42MB PNG image to 185kb in the Real World with virtually no loss in Visible Quality

▪ JPEG does not support Transparency

▪ Lossy Compression for Network pulled resources is the way to go for everything that is not a Photo app (Ok, even a Photo Gallery... maybe not an editor)

▪ Saves MEMORY so you don’t get the dreaded OOME (OutofMemoryError)

▪ WebP is a Combo of the best of JPEG and PNG since it supports Transparency and High Compression, but does not work for iPhones or universal Mobile Web (so, not a great possibility for converged APIs)

▪ You can compress PNG lossy and losslessly, but it never quite gets to JPEG

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Filtering your Images

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ARGB_8888 ARGB_4444 RGB_565

Transparency X X

Number of Bits 32 16 16

Full Color (nice Gradients)

X X

Space on Image Memory Load (def.)

SAME SAME SAME

● ARGB_4444 and RGB_565 will be about the same in size (Data in Transit) ● ARGB_4444 is ideal for web icon assets with minimal color gradients and

needing Transparency ● No need of Transparency? RGB_565 is always ideal. ● Android will always load images into the same amount of memory,

regardless of compression, so use the Bitmap Options tools to save Memory too

Types of Images

JPEG (or WebP) whenever possible (no Transparency needed)

ARGB_4444 for Iconography assets pulled from the network

Compress all your images (once)

Compress all your images (twice)

Compress all your images (three times a …) even PNGcrush!

Don’t be afraid to compress Lossy (especially with large images like 5MP+ Camera captured images, Google Photos does it!)

Compression on the Network != Compression in your Heap (do both)

Design your APIs to work with Screens of Many sizes

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TL:DR Image Filtering

▪ ADJUST YOUR ASSETS BASED ON YOUR NETWORK TYPE!!!!!

▪ Very Simple, just use the BroadcastReceiver class I have posted here: https://goo.gl/A5P1U3

▪ AND Facebook has an awesome DYNAMIC downstream bandwidth connection class library that you can use here : https://goo.gl/I7YLOE which can also be combined with their YEARCLASS library here: https://goo.gl/Ztgxik

▪ That way you can dynamically adjust your API requests

for quality because SPEED MATTERS.

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Tracking Your Network Type

Example Code (Combine and expand)

https://github.com/childofthehorn/network_classification_android

● Allows you to account for Multiple Screen sizes without skewing

● Dynamic Quality adjustment based on networks (Bigger screens can go down)

● Never get larger images than what you need

● Build based off of the devices you want to support.

● iPhones can also be accounted for in the Android sizing

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Structuring Images for Speed

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Ratio : 0.56:1 (16:9)

Devices : iPhone 5/6/6+, Samsung 3/4/5/6 (Android Devices with Hardware buttons)

HIGH Width : 1440 Height : 2560 MEDIUM Width : 1080 Height : 1920 LOW Width : 720 Height : 1280

Ratio : 0.63:1

Devices : iPhone 4, OnePlus 1/2, Nexus 5/5x/6/6p/7(2013)/7(2014), Moto X, G, E (2013-2015) (Android devices with software buttons)

HIGH Width : 1440 Height : 2268 MEDIUM Width : 1080 Height : 1701 LOW Width : 720 Height : 1134

Ratio : 0.81:1

Devices : Nexus 9, Samsung Tab S2, ZTE, Alcatel OneTouch phones (Prepaid smartphones less than $100)),

HIGH Width : 1536 Height : 1904 MEDIUM Width : 1050 Height : 1400 LOW Width : 640 Height : 800

Qualities BY network type

Serialized data types JSON

• Most popular, most APIs are formatted like this

• Easy to use libraries like RetroFit and Android Volley

• Still somewhat human-readable

XML

• Very Human-readable and alterable

• LOTS of type-casting overhead, LEAST EFFICIENT

PROTOBUFFERS

• Natively Supported on Android, but totally platform neutral (use with any Language or Platform, even iOS, Web, and Socket connections)

• Most efficient, but still popular way

• OMG Retrofit works here too now, so try for a combo when you can

• Must have formatted data that meets the expected format almost exactly, not a lot of error handling here, but Square has provided a tool for easy Conversion and generating code : https://github.com/square/wire

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Batching your Data is one of the easiest ways to optimize your usage of Cellular data.

Bundle Yourself

• Wait to offload large datasets ’til the user is on Wifi and hopefully charging as well (metrics and user behavior)

• JSON is not very efficient (XML is way worse), see if it is possible to switch to buffered data or binary files. Even CSV is more efficient...I know, right?

• Bundle your requests and waits together (promotional notifications and asset updates) this will give your user up to date data before they even launch the app without using more battery or network data!

Bundle Together

▪ GCMNetworkManager makes it easy to do this

(https://goo.gl/ThFuyo)23

Data Batching

1. Use lower quality images in low quality networks

2. Time to User matters (you only have a few hundred milliseconds)

3. Allow users to dictate resources and run in a low-usage network mode (best performance vs. best quality)

4. You can handle virtually all resources with just 3 aspect ratios for all of Android and iOS, as well as mobile web (Spiffy!)

5. Change your API requests to ProtoBuffers (Best) and JSON if possible

6. Batching your individual application data together and offload to high speed networks when possible

7. Bundle as a system with GcmNetworkManager

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TL:DR API Structure

THANKS

▪ The Home Depot DTC ▪ Google Developers ▪ Dallas Android Developers ▪ Android Performance Patterns ▪ ATT ▪ WireShark ▪ Big Android BBQ Team / IDEAA

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