Just as with the new Oracle 12c R1 lock types it’s time to take a quick look at the new enqueue waits in 12c. Oracle 11.2.0.3 had a total of 304 enqueue waits. 12.1 has a total of 418. A lot of work seems also to have happened on ASM in this release. The amount of new enqueues per group looks as follows:
| Group | Amount |
| ASM Enqueue | 16 |
| Enqueue-Cross SCN | 12 |
| Backup/Restore | 11 |
| Queue Ptning global enq | 8 |
| Being Written Redo Log | 8 |
| SGA Log-Bkt Flush | 6 |
| AM Container | 5 |
| Media Recovery | 5 |
| OLS groups | 4 |
| Instance Recovery | 3 |
| AVM RTA Access | 3 |
| AM Contained File Identification | 3 |
| Privilege Capture API | 2 |
| Queue table enqueue | 2 |
| Label Security Profile | 2 |
| RFS Logminer FLC | 2 |
| Data Guard Broker | 2 |
| IOServer File | 2 |
| Queue Partitioning local enqueue | 2 |
| Column Key | 1 |
| Flush Stat | 1 |
| Pluggable Database | 1 |
| SGA Log Operation | 1 |
| AM Group Rebuild/Validate | 1 |
| Real-Time ADDM Flood Control | 1 |
| AM Contained File Resize | 1 |
| PDB DDL Operations | 1 |
| non durable sub bmap alloc | 1 |
| CBAC Master Lock | 1 |
| IOServer Client | 1 |
| PDB Instance State | 1 |
| Oracle File System Operation | 1 |
| KJCI Serialization Enqueue | 1 |
| Spillover Audit files | 1 |
| Application Continuity | 1 |
| File Set / Dictionary Check | 1 |
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