a special Packet size affects latency

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- [ ] Bug exists Release Version 1.2.3 ( Master Branch)

I'm doing a test on latency under fixed TPS
I use guava's ratelimiter to limit TPS, which is now 10000 / s.
The server uses mosquito
The consumer, production and mosquito are on the same server.
We count the delays from the production end to mosquito and then to the consumer end.

I found a very strange phenomenon.
When the packet size is 116 (including 116), the delay is kept at about 2ms.
But when the packet size is larger than 116, for example, 117, the delay rises to about 8ms.
But as the packet size increases, the latency decreases.
The only difference between two tests is the size of the package.

116 may be a very magical number? I'm not sure.
Can someone help me to analyze the possible causes for further testing?

No source files or tests are identified. Start by reproducing the latency measurements with Guava's RateLimiter at 10,000 TPS and the stated Mosquitto setup, comparing packet sizes 116, 117, and larger values; done requires identifying and documenting the cause of the latency change.

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