app: Reduce RAM requirements when conn manager is disabled

Now that connection manager is removed, the RAM requirements
are lower. This patch reduces buffers and stacks to values that
should be sufficient for Wi-Fi and CoAP.

Signed-off-by: Jan Tore Guggedal <jantore.guggedal@nordicsemi.no>

Author: jtguggedal

app/boards/thingy91x_nrf9151_ns.conf

@@ -30,7 +30,6 @@ CONFIG_NRF70_BH_WQ_STACK_SIZE=1024
 CONFIG_NRF70_IRQ_WQ_STACK_SIZE=1024
 # Scan only using offload API
 CONFIG_WIFI_NM_WPA_SUPPLICANT=n
-CONFIG_NET_STATISTICS_WIFI=y
 
 # Wifi scan requires extended heap size
 # Heap allocations should be changed when CONFIG_LOCATION_METHOD_WIFI_SCANNING_RESULTS_MAX_CNT

app/prj.conf

@@ -29,7 +29,7 @@ CONFIG_HEAP_MEM_POOL_SIZE=12288
 CONFIG_HEAP_MEM_POOL_IGNORE_MIN=y
 CONFIG_SYSTEM_WORKQUEUE_STACK_SIZE=1408
 
-# Enable Networking and Connection Manager.
+# Enable Networking
 CONFIG_NETWORKING=y
 CONFIG_NET_SOCKETS=y
 
@@ -172,32 +172,27 @@ CONFIG_LOCATION_REQUEST_DEFAULT_GNSS_VISIBILITY_DETECTION=y
 CONFIG_LTE_NETWORK_MODE_LTE_M_NBIOT_GPS=y
 CONFIG_NRF_CLOUD_AGNSS=y
 
-# For nRF9160 the default is socket interface
-CONFIG_NET_DEFAULT_IF_ETHERNET=y
-CONFIG_MBEDTLS=n
-
-# Networking
-CONFIG_NET_L2_ETHERNET=y
-CONFIG_NET_NATIVE=y
+# Minimal networking for LTE offloaded sockets + CoAP + WiFi scan
 CONFIG_NET_IPV4=y
-CONFIG_NET_DHCPV4=y
-CONFIG_NET_STATISTICS=y
-CONFIG_NET_STATISTICS_USER_API=y
-CONFIG_NET_CONTEXT_SYNC_RECV=y
+CONFIG_NET_IPV6=n
+CONFIG_NET_NATIVE=y
+CONFIG_NET_DHCPV4=n
 
-# Memory configurations
+# Network buffers and packets (need enough for concurrent WiFi scan + CoAP)
 CONFIG_NET_BUF_RX_COUNT=8
 CONFIG_NET_BUF_TX_COUNT=8
-CONFIG_NET_PKT_RX_COUNT=1
-CONFIG_NET_PKT_TX_COUNT=1
-CONFIG_NET_TX_STACK_SIZE=512
-CONFIG_NET_RX_STACK_SIZE=512
-CONFIG_NET_TC_TX_COUNT=1
-CONFIG_NET_MAX_CONTEXTS=5
+CONFIG_NET_PKT_RX_COUNT=4
+CONFIG_NET_PKT_TX_COUNT=4
+
+# Network thread stack sizes (need headroom for CoAP/DTLS processing)
+CONFIG_NET_TX_STACK_SIZE=1024
+CONFIG_NET_RX_STACK_SIZE=1024
 CONFIG_NET_MGMT_EVENT_STACK_SIZE=1280
 
-# Needed due to using connectivity manager
-CONFIG_NET_IF_MAX_IPV6_COUNT=2
+# Network resources (multiple contexts needed for CoAP + WiFi operations)
+CONFIG_NET_TC_TX_COUNT=1
+CONFIG_NET_MAX_CONTEXTS=5
+CONFIG_NET_MAX_CONN=4
 CONFIG_NET_IF_MAX_IPV4_COUNT=2
 
 # For debugging purposes