esp32 GPIO interrupt latency

[jeromeh]

Hi,

I'm using a GPIO pin as a external interrupt, responding to negedge events. A event handler is registered and can be called correctly, but the interrupt latency seems pretty unpridictable.

I'm setting another GPIO pin to high when entering the event handler, and clears it before leaving the handler. Comparing the waveform in the scope, I'm seeing the 1st interrupt latency is around tens of us, and the 2nd interrupt seems to be around 1.5ms, and 3rd is around 6ms....

Is there any known issue related to external interrupt through GPIO? or anything special need to be done to reduce ISR latency? Thanks,

[jeromeh]

oh...I realized that it might because I'm using a mongoose-os api to setup the interrupt handler...and there is a queue used by mongoose-os might causing problem like this.