TextMesh Pro Does TMP cache the content text ?

I found when I send the same text to TMP, the first time will take same time , but the second time takes little time .
So I guess TMP use some cache policy to cache every single character so when the same content is set again, it will not build the new text mesh ?

 

TMP does check if the text or any other properties have changed and if everything is the same, it won't regenerate the text object.

Independently of that, the first time a text object is generated, some buffers need to be allocated which does add some overhead. However, once these have been allocated (in blocks) and provided the length of the text doesn't change and exceed the capacity of the new buffer, the subsequent generations will be faster.