V$PROCESS displays information about the currently active processes. While the LATCHWAIT column indicates what latch a process is waiting for, the LATCHSPIN column indicates what latch a process is spinning on. On multi-processor machines, Oracle processes will spin on a latch before waiting on it.
| Column | Datatype | Description |
|---|---|---|
ADDR |
RAW(4 | 8) |
Address of the process state object |
PID |
NUMBER |
Oracle process identifier |
SPID |
VARCHAR2(24) |
Operating system process identifier |
USERNAME |
VARCHAR2(15) |
Operating system process username
Note: Any two-task user coming across the network has "-T" appended to the username. |
SERIAL# |
NUMBER |
Process serial number |
TERMINAL |
VARCHAR2(30) |
Operating system terminal identifier |
PROGRAM |
VARCHAR2(48) |
Program in progress |
TRACEID |
VARCHAR2(255) |
Trace file identifier |
TRACEFILE |
VARCHAR2(513) |
Trace file name of the process |
BACKGROUND |
VARCHAR2(1) |
1 for a background process; NULL for a normal process |
LATCHWAIT |
VARCHAR2(8) |
Address of the latch the process is waiting for; NULL if none |
LATCHSPIN |
VARCHAR2(8) |
Address of the latch the process is spinning on; NULL if none |
PGA_USED_MEM |
NUMBER |
PGA memory currently used by the process |
PGA_ALLOC_MEM |
NUMBER |
PGA memory currently allocated by the process (including free PGA memory not yet released to the operating system by the server process) |
PGA_FREEABLE_MEM |
NUMBER |
Allocated PGA memory which can be freed |
PGA_MAX_MEM |
NUMBER |
Maximum PGA memory ever allocated by the process |