v4 Performance Tips

Global

Only optimize when you need to! PIXI can handle a fair amount of content off the bat.
The WebGL renderer is way faster than the canvas renderer. Use WebGL where you can!
Be mindful of the complexity of your scene. The more objects you add the slower things will end up.
Pixi renders things from back to front in the order they appear in the scene.
Being mindful of this order can help, for example sprite / graphic / sprite / graphic is slower than sprite / sprite / graphic / graphic.
Some older mobile devices run things a little slower. passing in the option 'legacy:true' to the renderer can help with performance.
Culling, PIXI does not cull anything, we have left this to you and your application.

Use spritesheets where possible to minimize total textures.
Sprites can be batched with up to 16 different textures (dependent on hardware).
This is the fastest way to render content.
On older devices use smaller low res textures.
Add the extension @0.5x.png to the 50% scale-down so PIXI will double them automatically.
Draw order can be important.

Graphics fastest when they are not modified constantly (not including the transform, alpha or tint!).
Separate Graphic instances are not batched.
Using 300 or more graphics objects can be slow, in this instance use sprites, if you can create a texture to share between them.

Textures are automatically managed by a Texture Garbage Collector.
You can also manage them yourself by using texture.destroy().
If you plan to destroy more than one at once add a random delay to their destruction to avoid freezing.
Delay texture destroy if you plan to delete a lot of textures yourself.

Tinting is totally FREE in the WebGL renderer, there is literally no overhead. So go nuts!
Tinting has a one time setup cost when using the canvas renderer per texture. Animating tints can be slow on the canvas renderer.

Avoid changing it on every frame as this can be expensive (each time it draws to a canvas and then uploads to GPU)
Bitmap Text gives much better performance for dynamically changing text.
Text resolution matches the renderer resolution, to increase resolution yourself you can textDouble the font size & scale it down to 50%.

Masks can be expensive if too many are used. 100s of masks will really slow things down.
Axis aligned Rectangle Masks are the fastest (as the use scissor rect).
Graphics masks are second fastest (as they use the stencil buffer).
Sprite masks are the third fastest (they uses filters) - really expensive do not use too many in your scene!

Release memory : displayObject.filters = null.
If you know the size of them: displayObject.filterArea = new PIXI.Rectangle(x,y,w,h). This can speeds things up as it means the object does not need to be measured.
Filters are expensive. Using too many will start to slow things down!

Setting cacheAsBitmap to true turns an object into a sprite by caching it as a texture.
It has a one time cost when it is activated as it draws the object to a texture.
Avoid changing this on elements frequently.
If you have a complicated item that has lots of sprites / filters AND do not move then this will speed up rendering!
Do not need apply to sprites as they are already textures.
Do not use if the object where its children are constantly changing as this will slow things down!

Constantly getting the width and height of objects can be slow for complex objects.
Getting width and heights of Sprites is fast!
If an object does not change often, use and store the bounds of an object by calling myObject.getBounds()

If an object has no interactive children use interactiveChildren = false the interaction manager will then be able to avoid crawling through the object.
Set hitArea = new PIXI.Rectangle(x,y,w,h). As above should stop the interaction manager from crawling through the object.