The set of logs here are very good and show build up of requests from 10.0.0.6 (Media Room) and also from remote user (josephdixxxxx) and would need the /connections list and process dump at the time
The new diagnostics you PM’ed me for the 29th July do not show any deadlock and no 503s.
When you took the /connections list, the logs show that requests were being handled ok and no deadlock
Jul 29, 2019 22:06:31.365 [11152] DEBUG - Request: [127.0.0.1:58352 (Loopback)] GET /hubs/home/recentlyAdded?type=1&includeExternalMedia=1 (13 live) Page 16-50 GZIP Signed-in Token (Chewbaccaman)
Jul 29, 2019 22:06:31.369 [9208] DEBUG - Request: [127.0.0.1:58344 (Loopback)] GET /hubs/home/recentlyAdded?type=2&includeExternalMedia=1 (13 live) Page 16-50 GZIP Signed-in Token (Chewbaccaman)
Jul 29, 2019 22:06:31.420 [14132] DEBUG - Completed: [127.0.0.1:58352] 200 GET /hubs/home/recentlyAdded?type=1&includeExternalMedia=1 (13 live) GZIP Page 16-50 54ms 15236 bytes (pipelined: 4)
Jul 29, 2019 22:06:31.455 [14132] DEBUG - Completed: [127.0.0.1:58344] 200 GET /hubs/home/recentlyAdded?type=2&includeExternalMedia=1 (13 live) GZIP Page 16-50 86ms 16720 bytes (pipelined: 8)
Jul 29, 2019 22:06:54.401 [18204] DEBUG - Request: [127.0.0.1:58398 (Loopback)] GET /channels/all (5 live) GZIP Signed-in Token (Chewbaccaman)
Jul 29, 2019 22:06:54.404 [14132] DEBUG - Completed: [127.0.0.1:58398] 200 GET /channels/all (5 live) GZIP 2ms 712 bytes (pipelined: 1)
Jul 29, 2019 22:06:54.419 [18204] DEBUG - Request: [127.0.0.1:58398 (Loopback)] GET /photo/:/transcode?url=%2F%3A%2Fplugins%2Fcom.plexapp.plugins.unsupportedappstore%2Fresources%2Ficon-default.png%3Ft%3D1420494167%26X-Plex-Token%3Dxxxxxxxxxxxxxxxxxxxx&width=188&height=188&minSize=1 (6 live) GZIP Signed-in Token (Chewbaccaman)
Jul 29, 2019 22:06:54.421 [11244] DEBUG - Request: [127.0.0.1:58399 (Loopback)] GET /photo/:/transcode?url=%2F%3A%2Fplugins%2Fcom.plexapp.plugins.WebTools%2Fresources%2FWebTools.png%3Ft%3D1461650852%26X-Plex-Token%3Dxxxxxxxxxxxxxxxxxxxx&width=188&height=188&minSize=1 (6 live) GZIP Signed-in Token (Chewbaccaman)
Jul 29, 2019 22:06:54.442 [14132] DEBUG - Completed: [127.0.0.1:58398] 200 GET /photo/:/transcode?url=%2F%3A%2Fplugins%2Fcom.plexapp.plugins.unsupportedappstore%2Fresources%2Ficon-default.png%3Ft%3D1420494167%26X-Plex-Token%3Dxxxxxxxxxxxxxxxxxxxx&width=188&height=188&minSize=1 (6 live) GZIP 22ms 10222 bytes (pipelined: 2)
Jul 29, 2019 22:06:54.453 [14132] DEBUG - Completed: [127.0.0.1:58399] 200 GET /photo/:/transcode?url=%2F%3A%2Fplugins%2Fcom.plexapp.plugins.WebTools%2Fresources%2FWebTools.png%3Ft%3D1461650852%26X-Plex-Token%3Dxxxxxxxxxxxxxxxxxxxx&width=188&height=188&minSize=1 (6 live) GZIP 32ms 32598 bytes (pipelined: 1)
Jul 29, 2019 22:07:24.870 [20412] DEBUG - Request: [10.0.0.13:58407 (Subnet)] GET /status/sessions (5 live) Signed-in Token (Chewbaccaman)
Jul 29, 2019 22:07:24.871 [20924] DEBUG - Completed: [10.0.0.13:58407] 200 GET /status/sessions (5 live) 1ms 292 bytes (pipelined: 1)
Jul 29, 2019 22:07:29.551 [3040] DEBUG - Request: [[::1]:58415 (Loopback)] GET /connections (6 live) GZIP Signed-in Token (Chewbaccaman)
Jul 29, 2019 22:07:29.553 [20924] DEBUG - Completed: [[::1]:58415] 200 GET /connections (6 live) GZIP 2ms 746 bytes (pipelined: 1)
So would need to wait until you have a repeat of the error 503s as you had on the 21st July and capture the deadlock diagnostics
