oeSenc loading and unloading charts continuously

[jongough]

I am running OCPN(5.2) with oeSenc (4.0.10 & 4.2.15) charts on a Raspberry PI 3B and a Linux Mint XFCE machine. The PI is used for navigating most of the time due to its small power requirements. I have noticed that with both the above versions of oeSenc the charts are continuously loaded and unloaded until at some point it then locks the chart cache. The plugin also reports continuosly in the opencpn.log.

Examples from the log:

08:00:39.225 MESSAGE chartdb.cpp:277 Purging unused chart from cache: /home/pi/Charts/mishkapi3a-AU-2020-14/OC-61-8X7325.oeevc
08:00:39.357 MESSAGE chartdb.cpp:1346 Creating new chart
08:00:39.358 MESSAGE chartdb.cpp:1475 Initializing Chart /home/pi/Charts/mishkapi3a-AU-2020-14/OC-61-8X7325.oeevc
08:00:42.067 MESSAGE chartdb.cpp:277 Purging unused chart from cache: /home/pi/Charts/mishkapi3a-AU-2020-14/OC-61-8X7325.oeevc
08:00:42.181 MESSAGE chartdb.cpp:1346 Creating new chart
08:00:42.181 MESSAGE chartdb.cpp:1475 Initializing Chart /home/pi/Charts/mishkapi3a-AU-2020-14/OC-61-8X7325.oeevc
08:00:44.870 MESSAGE chartdb.cpp:277 Purging unused chart from cache: /home/pi/Charts/mishkapi3a-AU-2020-14/OC-61-8X7325.oeevc
08:00:44.977 MESSAGE chartdb.cpp:1346 Creating new chart
08:00:44.977 MESSAGE chartdb.cpp:1475 Initializing Chart /home/pi/Charts/mishkapi3a-AU-2020-14/OC-61-8X7325.oeevc
08:00:47.658 MESSAGE chartdb.cpp:277 Purging unused chart from cache: /home/pi/Charts/mishkapi3a-AU-2020-14/OC-61-8X7325.oeevc
08:00:47.767 MESSAGE chartdb.cpp:1346 Creating new chart
08:00:47.767 MESSAGE chartdb.cpp:1475 Initializing Chart /home/pi/Charts/mishkapi3a-AU-2020-14/OC-61-8X7325.oeevc
08:00:50.465 MESSAGE chartdb.cpp:277 Purging unused chart from cache: /home/pi/Charts/mishkapi3a-AU-2020-14/OC-61-8X7325.oeevc
08:00:50.594 MESSAGE chartdb.cpp:1346 Creating new chart
08:00:50.594 MESSAGE chartdb.cpp:1475 Initializing Chart /home/pi/Charts/mishkapi3a-AU-2020-14/OC-61-8X7325.oeevc

and

08:25:24.571 MESSAGE chartdb.cpp:1299 OpenChartUsingCache: type 8 /home/pi/Charts/mishkapi3a-AU-2020-14/OC-61-351824.oeevc
08:25:24.571 MESSAGE chartdb.cpp:1169 Searching chart cache for oldest entry
08:25:24.571 MESSAGE chartdb.cpp:1189 Oldest unlocked cache index is 0, delta t is 2
08:25:24.571 MESSAGE chartdb.cpp:277 Removing oldest chart from cache: /home/pi/Charts/mishkapi3a-AU-2020-14/OC-61-351034.oeevc
08:25:24.631 MESSAGE chartdb.cpp:1346 Creating new chart
08:25:24.639 MESSAGE chartdb.cpp:1475 Initializing Chart /home/pi/Charts/mishkapi3a-AU-2020-14/OC-61-351824.oeevc
08:25:25.568 MESSAGE chartdb.cpp:1194 All chart in cache locked, size: 3
08:25:28.125 MESSAGE chartdb.cpp:1194 All chart in cache locked, size: 3
08:25:30.151 MESSAGE chartdb.cpp:1194 All chart in cache locked, size: 3
08:25:32.177 MESSAGE chartdb.cpp:1194 All chart in cache locked, size: 3
08:25:34.205 MESSAGE chartdb.cpp:1194 All chart in cache locked, size: 3
08:25:36.234 MESSAGE chartdb.cpp:1194 All chart in cache locked, size: 3
08:25:38.261 MESSAGE chartdb.cpp:1194 All chart in cache locked, size: 3

I have attached the full log.

I believe this is overloading the PI as it becomes unresponsive to keyboard and mouse input. I also get numerous 'Resetting GPU' messages on the pi which may or may not be related to this issue.

opencpn.log.gz