“Your system has run out of application memory.” Springboard leak?

I have a problem with system run out of application memory last days. All my applications are frozen after the system message, and the only way to work again is to make a cold reboot with button. I didn't install any new software, and Springboard is acting like crazy (I think it's the main source of leak since I am able to force Springboard to quit in Activity Monitor and somehow I can use my Macbook Pro for a few minutes after that). I have 360GB available on my system disk and 16GB RAM. MacOS Sierra, 10.12.6. Does anyone have this issue, and how did you solve it?