Same issue here. I have done tons of trouble shooting over the past few weeks and am very certain it is connected to external hard drives. On Catalina the issue even resulted in catastrophic crashes that rebooted in Internet Recovery mode to reinstall everything and wipe the drive. I have two external drives connected. One is APFS one is Journaled. It happens on two different machines for me when having the same hard drives connected. No external drives, no problem. Would love to see this fixed. Here's my crash report from the non fatal crashes: panic(cpu 2 caller 0xffffff8021f6ea25): userspace watchdog timeout: no successful checkins from com.apple.logd in 120 seconds service returned not alive with context : unresponsive dispatch queue(s): com.apple.firehose.io-wl  service: com.apple.logd, total successful checkins since load (27250 seconds ago): 2714, last successful checkin: 120 seconds ago service: com.apple.WindowServer, total successful checkins since load (27220 seconds ago): 2722, last successful checkin: 0 seconds ago Backtrace (CPU 2), Frame : Return Address 0xffffffb0cb923670 : 0xffffff801ecb9aed  0xffffffb0cb9236c0 : 0xffffff801edfc6e3  0xffffffb0cb923700 : 0xffffff801edecd1a  0xffffffb0cb923750 : 0xffffff801ec5ea2f  0xffffffb0cb923770 : 0xffffff801ecb938d  0xffffffb0cb923890 : 0xffffff801ecb9678  0xffffffb0cb923900 : 0xffffff801f4be434  0xffffffb0cb923970 : 0xffffff8021f6ea25  0xffffffb0cb923980 : 0xffffff8021f6e678  0xffffffb0cb9239a0 : 0xffffff801f44569e  0xffffffb0cb9239f0 : 0xffffff8021f6dab4  0xffffffb0cb923b20 : 0xffffff801f44f86b  0xffffffb0cb923c80 : 0xffffff801eda7d81  0xffffffb0cb923d90 : 0xffffff801ecbf0e7  0xffffffb0cb923e00 : 0xffffff801ec95905  0xffffffb0cb923e60 : 0xffffff801ecad012  0xffffffb0cb923ef0 : 0xffffff801edd0ec3  0xffffffb0cb923fa0 : 0xffffff801ec5f216        Kernel Extensions in backtrace:          com.apple.driver.watchdog(1.0)[7AE04EA4-D026-39A0-B2D5-5C9E4EE72967]@0xffffff8021f6d000->0xffffff8021f6efff Process name corresponding to current thread: watchdogd Mac OS version: 20C69 Kernel version: Darwin Kernel Version 20.2.0: Wed Dec  2 20:39:59 PST 2020; root:xnu-7195.60.75~1/RELEASEX8664 Kernel UUID: 82E2050C-5936-3D24-AD3B-EC4EC5C09E11 KernelCache slide: 0x000000001ea00000 KernelCache base:  0xffffff801ec00000 Kernel slide:      0x000000001ea10000 Kernel text base:  0xffffff801ec10000 _HIB  text base: 0xffffff801eb00000 System model name: iMac17,1 (Mac-B809C3757DA9BB8D) System shutdown begun: NO Panic diags file available: YES (0x0) Hibernation exit count: 0 System uptime in nanoseconds: 27255352600028 Last Sleep:           absolute           basetsc          basenano   Uptime  : 0x000018c9e19c287b   Sleep   : 0x0000000000000000 0x0000000000000000 0x0000000000000000   Wake    : 0x0000000000000000 0x00000016dd24ed82 0x0000000000000000 last started kext at 4162244807412: >usb.!UUserHCI 1 (addr 0xffffff7fbf59d000, size 98304) last stopped kext at 26683584986979: >usb.!UUserHCI 1 (addr 0xffffff7fbf59d000, size 98304) loaded kexts:!ATopCaseHIDEventDriver 4020.6AudioAUUC 1.70 @fsplaceholder 1.13.2 @filesystems.autofs 3.0 @fileutil 20.036.15AGPM 119!APlatformEnabler 2.7.0d0X86PlatformShim 1.0.0!AUpstreamUserClient 3.6.8 @kext.AMDFramebuffer 4.0.2!AMikeyHIDDriver 131 @kext.AMDRadeonX4000 4.0.2 @kext.AMDRadeonServiceManager 4.0.2!AMikeyDriver 283.15!A!ISKLGraphics 16.0.1!AGraphicsDevicePolicy 6.2.2!AHDA 283.15!A!IPCHPMC 2.0.1!ASMCLMU 212 @AGDCPluginDisplayMetrics 6.2.2!A!ISKLGraphicsFramebuffer 16.0.1pmtelemetry 1LuaHardwareAccess 1.0.16 |IOUserEthernet 1.0.1 |IO!BSerialManager 8.0.2f9 @DontStealMacOS_X 7.0.0!AHV 1!ADiskImages2 1!A!ISlowAdaptiveClocking 4.0.0 |Broadcom!B20703USBTransport 8.0.2f9!AMCCSControl 1.14 @kext.AMD9000!C 4.0.2eficheck 1!AThunderboltIP 4.0.3 |SCSITaskUserClient 436.40.6 @filesystems.tmpfs 1 @filesystems.hfs.kext 556.60.1 @BootCache 40 @!AFSCompression.!AFSCompressionTypeZlib 1.0.0 @!AFSCompression.!AFSCompressionTypeDataless 1.0.0d1 @filesystems.apfs 1677.60.23 |!ABCM5701Ethernet 11.0.0!ASDXC 1.9.0AirPort.BrcmNIC 1400.1.1!AAHCIPort 346 @private.KextAudit 1.0!AACPIButtons 6.1!ARTC 2.0!ASMBIOS 2.1!AACPIEC 6.1!AAPIC 1.7 @!ASystemPolicy 2.0.0 @nke.applicationfirewall 310 |IOKitRegistryCompatibility 1 |EndpointSecurity 1!AHIDKeyboard 222!AMultitouchDriver 4400.28!AInputDeviceSupport 4400.35!AHS!BDriver 4020.6IO!BHIDDriver 8.0.2f9 @kext.triggers 1.0 @kext.AMDRadeonX4070HWLibs 1.0 @kext.AMDRadeonX4000HWServices 4.0.2!AGraphicsControl 6.2.2DspFuncLib 283.15 @kext.OSvKernDSPLib 529X86PlatformPlugin 1.0.0IOPlatformPlugin!F 6.0.0d8 |IOAccelerator!F2 439.52 |IOSerial!F 11 |IOAVB!F 900.12!ASMBusPCI 1.0.14d1 @plugin.IOgPTPPlugin 900.11 |IOEthernetAVB!C 1.1.0 @!AGPUWrangler 6.2.2 |IOSlowAdaptiveClocking!F 1.0.0!AHDA!C 283.15 |IOHDA!F 283.15 |IOAudio!F 300.6.1 @vecLib.kext 1.2.0 |Broadcom!BHost!CUSBTransport 8.0.2f9 |IO!BHost!CUSBTransport 8.0.2f9 |IO!BHost!CTransport 8.0.2f9 |IONDRVSupport 585!ASMBus!C 1.0.18d1 @kext.AMDSupport 4.0.2 @!AGraphicsDeviceControl 6.2.2 |IOGraphics!F 585!AThunderboltEDMSink 5.0.3usb.networking 5.0.0usb.!UHostCompositeDevice 1.2!AThunderboltDPOutAdapter 8.1.4!AThunderboltDPInAdapter 8.1.4!AThunderboltDPAdapter!F 8.1.4!AThunderboltPCIDownAdapter 4.1.1!ABSDKextStarter 3 |IOSurface 289.3 @filesystems.hfs.encodings.kext 1 |IOAHCIBlock!S 332!AThunderboltNHI 7.2.8 |IOThunderbolt!F 9.3.2 |IO80211!F 1200.12.2b1 |IOSkywalk!F 1mDNSOffloadUserClient 1.0.1b8corecapture 1.0.4 |IOAHCI!F 294 |IOUSB!F 900.4.2usb.!UXHCIPCI 1.2usb.!UXHCI 1.2!AEFINVRAM 2.1!AEFIRuntime 2.1 |IOSMBus!F 1.1 |IOHID!F 2.0.0 $!AImage4 3.0.0 |IOTimeSync!F 900.11 |IONetworking!F 3.4DiskImages 493.0.0 |IO!B!F 8.0.2f9 |IOReport!F 47 |IO!BPacketLogger 8.0.2f9 $quarantine 4 $sandbox 300.0 @kext.!AMatch 1.0.0d1 |CoreAnalytics!F 1!ASSE 1.0!AKeyStore 2!UTDM 511.60.2 |IOUSBMass!SDriver 184.40.6 |IOSCSIBlockCommandsDevice 436.40.6 |IO!S!F 2.1 |IOSCSIArchitectureModel!F 436.40.6!AMobileFileIntegrity 1.0.5 @kext.CoreTrust 1!AFDEKeyStore 28.30!AEffaceable!S 1.0!ACredentialManager 1.0KernelRelayHost 1 |IOUSBHost!F 1.2!UHostMergeProperties 1.2usb.!UCommon 1.0!ABusPower!C 1.0!ASEPManager 1.0.1IOSlaveProcessor 1!AACPIPlatform 6.1!ASMC 3.1.9 |IOPCI!F 2.9 |IOACPI!F 1.4watchdog 1 @kec.pthread 1 @kec.corecrypto 11.1 @kec.Libm 1