I installed Kali Linux RaspberryPi 2 (v1.2), 3 and 4 64-Bit on my Raspberry Pi 4 with 4Gb RAM.
All is running very well but I frequently experience a freeze, about 10 seconds of total interruption of all applications.
I tried to change SD card and to keep CPU cold but without success.
Before and during the freeze the system log itself is freezed. A little before I find some messages regarding to wifi but I think that they are not pertinent because they always periodically appear.
kernel: [41757.613100] brcmfmac: _brcmf_set_multicast_list: Setting allmulti failed, -110 kernel: [41760.173154] brcmfmac: _brcmf_set_multicast_list: Setting BRCMF_C_SET_PROMISC failed, -110 wpa_supplicant: wlan0: CTRL-EVENT-SCAN-FAILED ret=-110 kernel: [41762.733156] brcmfmac: brcmf_run_escan: error (-110
I wonder if this is a problem of the 64bit kernel port or what?
Unfortunately I didn't find the reason for the freeze that occur mainly when I interact with GUIs. I followed the Dmitry Grigoryev's suggestion, wrote the script, tried to eliminate processes but the freeze remained.
At the end I installed official 32bit Raspbian and enriched it with all Kali Linux tools: no more freeze.
By the way, what the advantages of running a 64bit OS on a 4Gb RAM machine? But this is another question...