# Efficiency of Event vs Command Instruments

**URL:** <https://qa.fmod.com/t/efficiency-of-event-vs-command-instruments/18148>\
**Category:** FMOD Studio\
**Created:** [December 28, 2021, 8:45pm UTC](https://qa.fmod.com/t/efficiency-of-event-vs-command-instruments/18148 "2021-12-28T20:45:12Z")\
**Posts on this page:** 2\
**Page:** 1

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**Author:** ![TShermanWF](https://avatars.discourse-cdn.com/v4/letter/t/e19adc/32.png) [@TShermanWF](https://qa.fmod.com/u/TShermanWF)\
**Post date:** [December 28, 2021, 8:45pm UTC](https://qa.fmod.com/t/efficiency-of-event-vs-command-instruments/18148/1 "2021-12-28T20:45:12Z")

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Is there a computational difference between FMOD’s event vs command instruments?

Use example: I’d like to trigger the tail to a player weapon in a separate event but, since it can be spammed, I’m curious to know if an event instrument is less demanding than triggering the event start via a command instrument

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**Author:** ![jeff\_fmod](https://yyz2.discourse-cdn.com/flex036/user_avatar/qa.fmod.com/jeff_fmod/32/1766_2.png) [@jeff\_fmod](https://qa.fmod.com/u/jeff_fmod)\
**Post date:** [December 30, 2021, 12:50am UTC](https://qa.fmod.com/t/efficiency-of-event-vs-command-instruments/18148/2 "2021-12-30T00:50:24Z")

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I would expect there to be some negligible constant-time overhead to command instruments in that to play a sound with a command instrument results in 2 API calls- one to issue the command, and another to play the event. As the event count increases however there is the possibility of commands getting dropped due to command buffer overflow- which would make it more performant, but only because some commands aren’t being executed.  
For comparison, here is 100 events vs 100 commands:

 ![image](https://canada1.discourse-cdn.com/flex036/uploads/fmod/original/2X/0/0c272f74923cd24f5d3725321b7c46cbbc963409.png)  
You can see they have approximately the same cpu overhead- the update thread looks a little more stressed when playing 100 events.  
Here is 512 events vs 512 commands:  
 ![image](https://canada1.discourse-cdn.com/flex036/uploads/fmod/original/2X/6/6bf7d6ed155a7f646b8eb676275551d077c74985.png)  
You can see a significant reduction of about 50% in cpu when calling 512 commands, but there are warnings about the command buffer being resized, showing that the cpu reduction is actually a side effect of commands being dropped and events never being played.  
In any case, I would recommend trying each alternative, profiling both options, and basing your decision off of data collected for your specific use case.