Unity foundation 5-optimization strategy

Recommended reading

Reduce drawcall

drawcall Namely CPU towards GPU Interface for sending drawing commands , When objects of different materials are drawn on the screen , Need to be CPU Call the graph API （ OpenGL or direct3d ） Trigger graphics card drawing

1. Static objects of the same material , stay inspector Window tick static
2. Merge Atlas
   Using atlas can avoid the gap between tiles
3. Algorithm optimization
   …

GC Optimize

unity Using automatic memory management , It is divided into heap area and stack area , Memory reclamation in the stack area is fast , Performance optimization is mainly reflected in heap memory recycling .

Steps of heap memory allocation ：

1. Idle memory units are enough , No extra memory is allocated
2. Trigger garbage collection , Get more spare memory units , Reallocate memory
3. After recycling , Idle memory units are still not enough , Expand the size of heap memory , redistribution

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Operation steps of garbage collection ：

1. Check every stored variable in the heap
2. Whether the reference of variable is activated
3. Inactive variables are marked as recyclable
4. Remove the marked variable , Free memory

When to trigger garbage collection ：

1. When memory is allocated on the heap but there is not enough free memory
2. Different platforms automatically trigger GC
3. Enforcement GC

Optimization strategy

• Reduce GC Number of runs 、 Single run time
• Delay GC Running time of , For example, when the game pauses 、 Execute during scene switching GC

The specific methods

• Reduce heap memory allocation and reference allocation
• Reduce the frequency of heap memory allocation and recycling
• Objects that need to be generated and destroyed frequently , Using object pooling technology

other

• Avoid frequently creating strings
• Reduce packing operations
• In process operation , Avoid returning new parameters , for example yield return new WaitForSeconds(1f);