I think i have similar problems.
I have every 10 sec this
Oct 13 23:54:55 iMac27 kernel[0]: Sandbox: sandboxd(2164) deny mach-lookup com.apple.coresymbolicationd
Oct 13 23:54:55 iMac27.local sandboxd[2164] ([2131]): WebProcess(2131) deny mach-lookup ATS Query Port 216
Oct 13 23:55:03 iMac27 com.apple.launchd.peruser.502[132] (com.apple.ubd[2165]): Exited with code: 254
Oct 13 23:55:03 iMac27 com.apple.launchd.peruser.502[132] (com.apple.ubd): Throttling respawn: Will start in 10 seconds
Oct 13 23:55:13 iMac27 com.apple.launchd.peruser.502[132] (com.apple.ubd[2166]): Exited with code: 254
Oct 13 23:55:13 iMac27 com.apple.launchd.peruser.502[132] (com.apple.ubd): Throttling respawn: Will start in 10 seconds
Oct 13 23:55:23 iMac27 com.apple.launchd.peruser.502[132] (com.apple.ubd[2167]): Exited with code: 254
Oct 13 23:55:23 iMac27 com.apple.launchd.peruser.502[132] (com.apple.ubd): Throttling respawn: Will start in 10 seconds
Oct 13 23:55:33 iMac27 com.apple.launchd.peruser.502[132] (com.apple.ubd[2168]): Exited with code: 254
Oct 13 23:55:33 iMac27 com.apple.launchd.peruser.502[132] (com.apple.ubd): Throttling respawn: Will start in 10 seconds
Oct 13 23:55:43 iMac27 com.apple.launchd.peruser.502[132] (com.apple.ubd[2169]): Exited with code: 254
Oct 13 23:55:43 iMac27 com.apple.launchd.peruser.502[132] (com.apple.ubd): Throttling respawn: Will start in 10 seconds
Oct 13 23:55:53 iMac27 com.apple.launchd.peruser.502[132] (com.apple.ubd[2170]): Exited with code: 254
Oct 13 23:55:53 iMac27 com.apple.launchd.peruser.502[132] (com.apple.ubd): Throttling respawn: Will start in 10 seconds
Oct 13 23:56:03 iMac27 com.apple.launchd.peruser.502[132] (com.apple.ubd[2171]): Exited with code: 254
Oct 13 23:56:03 iMac27 com.apple.launchd.peruser.502[132] (com.apple.ubd): Throttling respawn: Will start in 10 seconds
Oct 13 23:56:13 iMac27 com.apple.launchd.peruser.502[132] (com.apple.ubd[2172]): Exited with code: 254
Oct 13 23:56:13 iMac27 com.apple.launchd.peruser.502[132] (com.apple.ubd): Throttling respawn: Will start in 10 seconds
Oct 13 23:56:23 iMac27 com.apple.launchd.peruser.502[132] (com.apple.ubd[2173]): Exited with code: 254
Oct 13 23:56:23 iMac27 com.apple.launchd.peruser.502[132] (com.apple.ubd): Throttling respawn: Will start in 10 seconds
Oct 13 23:56:24 iMac27.local Disk Utility[2174]: ApplePersistence=NO
Oct 13 23:56:24 iMac27.local com.apple.SecurityServer[17]: Succeeded authorizing right 'system.burn' by client '/Applications/Utilities/Disk Utility.app' [2174] for authorization created by '/Applications/Utilities/Disk Utility.app' [2174] (B,0)
Oct 13 23:56:27 iMac27.local com.apple.SecurityServer[17]: Succeeded authorizing right 'com.apple.DiskManagement.internal.RepairPermissions' by client '/usr/sbin/diskmanagementd' [2175] for authorization created by '/Applications/Utilities/Disk Utility.app' [2174] (10000B,0)
Oct 13 23:56:34 iMac27 com.apple.launchd.peruser.502[132] (com.apple.ubd[2178]): Exited with code: 254
Oct 13 23:56:34 iMac27 com.apple.launchd.peruser.502[132] (com.apple.ubd): Throttling respawn: Will start in 10 seconds
Oct 13 23:56:44 iMac27 com.apple.launchd.peruser.502[132] (com.apple.ubd[2179]): Exited with code: 254
Oct 13 23:56:44 iMac27 com.apple.launchd.peruser.502[132] (com.apple.ubd): Throttling respawn: Will start in 10 seconds
Oct 13 23:56:54 iMac27 com.apple.launchd.peruser.502[132] (com.apple.ubd[2180]): Exited with code: 254
Oct 13 23:56:54 iMac27 com.apple.launchd.peruser.502[132] (com.apple.ubd): Throttling respawn: Will start in 10 seconds
Oct 13 23:57:04 iMac27 com.apple.launchd.peruser.502[132] (com.apple.ubd[2182]): Exited with code: 254
Oct 13 23:57:04 iMac27 com.apple.launchd.peruser.502[132] (com.apple.ubd): Throttling respawn: Will start in 10 seconds
Oct 13 23:57:14 iMac27 com.apple.launchd.peruser.502[132] (com.apple.ubd[2183]): Exited with code: 254
Oct 13 23:57:14 iMac27 com.apple.launchd.peruser.502[132] (com.apple.ubd): Throttling respawn: Will start in 10 seconds
Oct 13 23:57:24 iMac27 com.apple.launchd.peruser.502[132] (com.apple.ubd[2184]): Exited with code: 254
Oct 13 23:57:24 iMac27 com.apple.launchd.peruser.502[132] (com.apple.ubd): Throttling respawn: Will start in 10 seconds
Oct 13 23:57:34 iMac27 com.apple.launchd.peruser.502[132] (com.apple.ubd[2185]): Exited with code: 254
Oct 13 23:57:34 iMac27 com.apple.launchd.peruser.502[132] (com.apple.ubd): Throttling respawn: Will start in 10 seconds
Oct 13 23:57:44 iMac27 com.apple.launchd.peruser.502[132] (com.apple.ubd[2186]): Exited with code: 254
Oct 13 23:57:44 iMac27 com.apple.launchd.peruser.502[132] (com.apple.ubd): Throttling respawn: Will start in 10 seconds
Oct 13 23:57:54 iMac27 com.apple.launchd.peruser.502[132] (com.apple.ubd[2187]): Exited with code: 254
Oct 13 23:57:54 iMac27 com.apple.launchd.peruser.502[132] (com.apple.ubd): Throttling respawn: Will start in 10 seconds
Oct 13 23:57:58 iMac27.local com.apple.SecurityServer[17]: Succeeded authorizing right 'com.apple.DiskManagement.internal.RepairPermissions' by client '/usr/sbin/diskmanagementd' [2175] for authorization created by '/Applications/Utilities/Disk Utility.app' [2174] (10000B,0)
Oct 13 23:58:04 iMac27 com.apple.launchd.peruser.502[132] (com.apple.ubd[2189]): Exited with code: 254
Oct 13 23:58:04 iMac27 com.apple.launchd.peruser.502[132] (com.apple.ubd): Throttling respawn: Will start in 10 seconds
Oct 13 23:58:15 iMac27 com.apple.launchd.peruser.502[132] (com.apple.ubd[2191]): Exited with code: 254
Oct 13 23:58:15 iMac27 com.apple.launchd.peruser.502[132] (com.apple.ubd): Throttling respawn: Will start in 10 seconds
Oct 13 23:58:21 iMac27.local Console[2192]: ApplePersistence=NO
Oct 13 23:58:25 iMac27 com.apple.launchd.peruser.502[132] (com.apple.ubd[2193]): Exited with code: 254
Oct 13 23:58:25 iMac27 com.apple.launchd.peruser.502[132] (com.apple.ubd): Throttling respawn: Will start in 10 seconds
It happen today i think. I think i have a screwed up library folder with wrong permissions.