ASM Disk Group Interval (PI_PIDG)
- Organization of this page
Function
The ASM Disk Group Interval (PI_PIDG) record stores, at specific intervals, the performance data of the ASM disk managed by the ASM instance through which Oracle communicates. This is a multi-instance record.
To use this record to monitor the free space in a non-mirrored configuration, we recommend monitoring the Free Mbyte field. In a mirrored configuration, we recommend monitoring the Usable File Mbytes field.
Using an ASM disk group with a redundant mirroring configuration as an example, the field configuration pertaining to the free space in the ASM Disk Group Interval (PI_PIDG) is shown in the following figure.
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![[Figure]](GRAPHICS/ZUO05001.GIF)
- #1
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If a failure occurs in a mirrored ASM disk group, this capacity is needed for recovery. If this capacity is insufficient when a failure occurs, recovery might be impossible.
- #2
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This shows the space that can be used in a mirroring configuration. This is the value obtained by subtracting the Required Mirror Free Mbytes value from the Free Mbytes value. In a redundant (duplicated) mirroring configuration, if the difference is 4 gigabytes, the Usable File Mbytes value is halved (2 gigabytes).
If this capacity is insufficient, a new file might not be created, or file redundancy might not be maintained.
Depending on the values of the Free Mbyte and Required Mirror Free Mbytes fields, the capacity might be a negative value.
- Notes
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The collection of the ASM Disk Group Interval (PI_PIDG) record is supported when the versions of both ASM and Oracle Database are 11.2.0 or later. Collection is not supported in version 11.1.0 or earlier.
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The capacity of the ASM disk group is calculated from the online ASM disks. As a result, the original capacity cannot be collected if any offline ASM disks exist.
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If the monitoring target is Oracle Database 12c Release 2 or later in a CDB configuration, this record stores performance data for all ASM disk group in the entire CDB, which are managed by the ASM instances through which Oracle communicates. The retrieved values will be same for both when monitoring PDBs and when monitoring the root container (CDB$ROOT).
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Default and changeable values
|
Item |
Default value |
Changeable |
|---|---|---|
|
Collection Interval |
3600 |
Y |
|
Collection Offset |
260 |
Y |
|
Log |
No |
Y |
|
LOGIF |
(Blank) |
Y |
|
Over 10 Sec Collection Time |
No |
N |
ODBC key fields
PI_PIDG_NAME
Lifetime
From creation to deletion of the ASM disk group
Record size
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Fixed part: 678 bytes
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Variable part: 280 bytes
Fields
|
PFM - View name (PFM - Manager name) |
Description |
Summary |
Format |
Delta |
Supported version |
Data source |
|---|---|---|---|---|---|---|
|
Allocation Unit Size (ALLOCATION_UNIT_SIZE) |
Size of the allocation unit in bytes |
COPY |
ulong |
No |
Oracle 11g R2 or later |
V$ASM_DISKGROUP.ALLOCATION_UNIT_SIZE |
|
Cold Used Mbytes (COLD_USED_MBYTES) |
Size of used area (in megabytes) in the cold region |
AVG |
double |
No |
Oracle 11g R2 or later |
V$ASM_DISKGROUP.COLD_USED_MB |
|
Free % (FREE_PERC) |
Percentage of free space in the disk group |
AVG |
double |
No |
Oracle 11g R2 or later |
(FREE_MBYTES / TOTAL_MBYTES) * 100 |
|
Free Mbytes (FREE_MBYTES) |
Size of unused area (in megabytes) of the disk group |
AVG |
double |
No |
Oracle 11g R2 or later |
V$ASM_DISKGROUP.FREE_MB |
|
Group Number (GROUP_NUMBER) |
Cluster number assigned to the disk group |
COPY |
ulong |
No |
Oracle 11g R2 or later |
V$ASM_DISKGROUP.GROUP_NUMBER |
|
Hot Used % (PERCENT_HOT_USED) |
Percentage of use in the hot region |
AVG |
double |
No |
Oracle 11g R2 or later |
(V$ASM_DISKGROUP.HOT_USED_MB / (V$ASM_DISKGROUP.HOT_USED_MB + V$ASM_DISKGROUP.COLD_USED_MB) ) * 100 |
|
Hot Used Mbytes (HOT_USED_MBYTES) |
Size of used area (in megabytes) in the hot region |
AVG |
double |
No |
Oracle 11g R2 or later |
V$ASM_DISKGROUP.HOT_USED_MB |
|
Name (NAME) |
Disk group name |
COPY |
string(30) |
No |
Oracle 11g R2 or later |
V$ASM_DISKGROUP.NAME |
|
Offline Disks (OFFLINE_DISKS) |
Number of offline disks in the disk group |
AVG |
long |
No |
Oracle 11g R2 or later |
V$ASM_DISKGROUP.OFFLINE_DISKS |
|
Record Time (RECORD_TIME) |
Time that collection of the performance data stored in the record finished |
COPY |
time_t |
No |
Oracle 11g R2 or later |
Agent Collector |
|
Record Type (INPUT_RECORD_TYPE) |
Record name (always PIDG) |
COPY |
string(4) |
No |
Oracle 11g R2 or later |
Agent Collector |
|
Required Mirror Free Mbytes (REQUIRED_MIRROR_FREE_MBYTES) |
Capacity (in megabytes) needed for recovery |
AVG |
double |
No |
Oracle 11g R2 or later |
V$ASM_DISKGROUP.REQUIRED_MIRROR_FREE_MB |
|
Restore Area Lack (RESTORE_AREA_LACK) |
Indicates whether the capacity is sufficient for recovery. 1 is set if the capacity is insufficient. 0 is set if the capacity is sufficient. |
COPY |
short |
No |
Oracle 11g R2 or later |
V$ASM_DISKGROUP.FREE_MB >= V$ASM_DISKGROUP.REQUIRED_MIRROR_FREE_MB |
|
Sector Size (SECTOR_SIZE) |
Physical block size in bytes |
COPY |
ushort |
No |
Oracle 11g R2 or later |
V$ASM_DISKGROUP.SECTOR_SIZE |
|
Start Time (START_TIME) |
Start time for collection of the performance data stored in the record |
COPY |
time_t |
No |
Oracle 11g R2 or later |
Agent Collector |
|
State (STATE) |
Disk group status |
COPY |
string(11) |
No |
Oracle 11g R2 or later |
V$ASM_DISKGROUP.STATE |
|
Total Mbytes (TOTAL_MBYTES) |
Total capacity of the disk group (in megabytes) |
AVG |
double |
No |
Oracle 11g R2 or later |
V$ASM_DISKGROUP.TOTAL_MB |
|
Type (TYPE) |
Redundancy type of the disk group |
COPY |
string(6) |
No |
Oracle 11g R2 or later |
V$ASM_DISKGROUP.TYPE |
|
Usable File Mbytes (USABLE_FILE_MBYTES) |
Free space (in megabytes) that can be used in a mirroring configuration. This value can be negative. |
AVG |
double |
No |
Oracle 11g R2 or later |
V$ASM_DISKGROUP.USABLE_FILE_MB |
|
Usable File Free % (USABLE_PERC) |
Percentage of space necessary for restoration. When this percentage turns out to be a negative value, 0 is displayed instead. |
AVG |
double |
No |
Oracle 11g R2 or later |
(USABLE_FILE_MBYTES / TOTAL_MBYTES) * 100 |
|
Used Mbytes (USED_MBYTES) |
Size of used area (in megabytes) of the disk group |
AVG |
double |
No |
Oracle 11g R2 or later |
V$ASM_DISKGROUP.TOTAL_MB - V$ASM_DISKGROUP.FREE_MB |
|
Voting Files (VOTING_FILES) |
Indicates whether a voting file is included in the disk group. Y is set if the voting file is included. In other cases, N is set. |
COPY |
string(1) |
No |
Oracle 11g R2 or later |
V$ASM_DISKGROUP.VOTING_FILES |