Here yo go ...
++ Compile date = Feb 25 2021 {AFNI_21.0.12:linux_ubuntu_16_64}
afni -no_detach -quiet -VAFNI_COMPRESSOR=
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afni -no_detach -quiet -VAFNI_AUTOGZIP=
YES
afni -no_detach -quiet -VAFNI_NOMMAP=
<BLANK>
time 3dROIstats -mask mask2.nii.gz func.nii.gz
File Sub-brick Mean_1
func.nii.gz 0[?] 9957.563410
func.nii.gz 1[?] 9947.920665
func.nii.gz 2[?] 9938.978018
func.nii.gz 3[?] 9942.901682
...
func.nii.gz 335[?] 10079.657652
func.nii.gz 336[?] 10037.459720
func.nii.gz 337[?] 10058.559225
real 2m28.275s
user 2m14.740s
sys 0m13.461s
++ Compile date = Jan 29 2020 {AFNI_20.0.04:linux_ubuntu_16_64}
~/abin_older/afni -no_detach -quiet -VAFNI_COMPRESSOR=
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~/abin_older/afni -no_detach -quiet -VAFNI_AUTOGZIP=
YES
~/abin_older/afni -no_detach -quiet -VAFNI_NOMMAP=
<BLANK>
time ~/abin_older/3dROIstats -mask mask2.nii.gz func.nii.gz
File Sub-brick Mean_1
func.nii.gz 0[?] 9957.563410
func.nii.gz 1[?] 9947.920665
func.nii.gz 2[?] 9938.978018
...
func.nii.gz 335[?] 10079.657652
func.nii.gz 336[?] 10037.459720
func.nii.gz 337[?] 10058.559225
real 0m0.531s
user 0m0.475s
sys 0m0.056s