it seems thank browser is being killed by oom killer

Hi again. Sorry for disturbing. Just one question. Maybe, you have some suggestion. I've got the issue with 'An unknown error has occurred'. What I observed during yesterday's run. I ran UI tests in 5 threads. The first 30-40 tests ran really quickly and stable. The next 20-30 are slower, the next 30 are really slow (I could observe via VNC that Dropdown was opened slowly, by pixels, text are typing symbol by symbol) and it finished by situation when pages are loaded so long and test failed due to timeout. I use Selenide browser configuration timeout 18 sec, default is 4. (Configuration.timeout = 18000;) It means that elements did not appear during 18 seconds, that is not normal behavior. Visible hanging is observed. Maybe I should verify some parameters or check memory, but the situation with memory when hanging occurred seems good. Sometimes CPU in one browser increases up to 100%-200%, but it happens for 1 second and after that situation is similar as on the screenshot. Thanks a lot.