MPU-9150 measurement timing

Couple of non-trivial questions.

First my setup. I have a MPU-9150 connected to a microcontroller. The INT line is used as DATA_READ. The FSYNC input is connected to something equivalent to the PPS pulse of a GPS, and read back as the LSB of the TEMP. The DLPF_CFG is set to 3. The sample rate is 1000Hz, the PLL is taken from Z axis gyro.

(1) The FSYNC input, where does it enter the pipeline ? Is it at sample time (i.e. before the LPF/HPF) ?

(2) Is there a good way to compute the measurement time of the GYRO from the DATA_READY event ? The LPF setting implies already a delay of 4.9ms. Are there any other delays ? Is there a more exact timing available ? I can measure the time delta between 2 DATA_READY events, so can the delay be expressed more directly as a fraction of that ?

(3) Is there another way to derive the measurement time as exact as possible ?

- Thomas