Increase LodDistanceCheckTime so you are checking LODs less often (for looping effects with LODMethod set to automatic). Set Fixed Bounds on your particle system so you do not calculate them each frame. Consider upgrading hardware of the physical server for better performance and optimize MySQL configurations based on the hardware specifications. Multithreading splits tasks into 'threads' where possible, and runs them in parallel across the cores of multi-core CPUs to potentially improve performance. Do a thorough review of queries sent to the server and optimize database structure/design and SQL query Evaluate the factors affecting MySQL performance as explained in the introduction. Replace Game Thread calculated particle effects with Static Mesh effects if possible. All of the above variables relate to the use of the GameBryo engine's multithreading capabilities. Remove expensive calculations such as collision, dynamic parameters, etc. to ensure the settings you are using are optimal, reduce collisions or the amount of particles/meshes colliding. Reduce lifetime (the amount of time particle evaluation is calculated) for some of your emitters.Д¬heck expensive calculations such as collision etc. Reduce the number of particle systems in the scene. Reduce particle emission counts on the systems being used. Specifically talking about UE4, there are a few ways to improve performance and reduce hitching. Turning off Control Flow Guard, in Exploit Protection, can help a bit. Problems with stuttering occur with lots of games, especially with DX12. Once you have identified Game Thread systems which are offenders, there are several paths to take. Since it's the most used game engine today, it's bound to have games that are optimization problems. The more unique emitters and modules in your system, and the more of those systems in your scene, the higher the Game Thread cost. It is important to remember that a particle system is the sum of the components (emitters/modules) which make up the effect.

If any thread goes over the 33ms and your particles are a suspected culprit, you can use the STAT PARTICLES command to gauge particle times on the different threads. If your target framerate is 30fps, all threads should remain below 33.3ms. Keep an eye on the different thread times. It is possible to monitor the different times updated by stat unit to see areas of the level with performance issues. The stat unit command displays the time spent for the current frame on the Game Thread, the time spent for the Render thread, and the time spent for the GPU. Press the **`** key and enter `stat unit` into the Console. One way to monitor for issues while playing through levels is to pull up the STAT UNIT debug overlay. First off, identifying where your effects are creating bottlenecks will go a long way towards optimizing the correct issue, thereby retaining visual integrity/quality.

There are several features of UE4 in place which allow effects artists to trouble shoot performance issues.

Identifying GPU, Render Thread, and Game Thread issues

Gamebryo engine terrible optimization