How to monitor pool (Max Pool Size=1000;)

Hi All, I want to know how to monitor pool (Max Pool Size=1000;)

Event Error messages: Service was unable to open new database connection when requested. TransactionManagerCommunicationException: Network access for Distributed Transaction Manager (MSDTC) has been disabled. Please enable DTC for network access in the security configuration for MSDTC using the Component Services Administrative tool. Connection string - Data Source=xyz;Initial Catalog=SolarWindsOrion;Persist Security Info=False;User ID=xyz;Password=*******;Max Pool Size=1000;Connect Timeout=20;Load Balance Timeout=120;Packet Size=4096;Application Name=SolarWinds.Alerting.Service@SolarWinds.Alerting.Service.exe;Workstation ID=ABC