Oracle Database / Sessions, Locks & Transactions
ORA-00020: investigate Oracle process exhaustion
New logins can fail when the instance cannot allocate another process slot. Existing connections may still let an authorized DBA collect evidence.
Environment and inputs: Oracle Database 19c baseline · SQL*Plus-compatible SQL unless RMAN, DGMGRL, ADRCI or a host shell is specified. Check release, patch level, edition and container first.
Start with this diagnostic
Use the stated SQL, RMAN, DGMGRL or host shell and replace sample names with approved targets. DBA and V$ views need authorized catalog access in the correct container. Do not grant broad privileges for an example.
SELECT resource_name, current_utilization, max_utilization, limit_value FROM v$resource_limit WHERE resource_name = 'processes';Read the result
The process limit applies to more than ordinary user sessions. Background and parallel processes can consume capacity as well.
Resolve and verify
Correlate the peak with connection storms, parallel work and pool changes. Stabilize the source of growth and plan supported process capacity with OS and memory limits.
Operational precautions
Do not repeatedly spawn administrative connections during exhaustion or assume unused sessions imply free process capacity.