Field

Description

DB instance

Name of the current database instance

This is the SAP-SID in non-RAC environments.

DB node

Host name of the selected DB node

This is the database server in non-RAC environments.

DB release

Release of the current database

Day, time

Current day and time

Start up at

Date and time when the current database instance started

Sec. since start

Seconds since start of the current database instance

Field

Description

Size

Size of the data buffer in KB

·        Non-RAC or RAC detail: data buffer size of the current instance

·        RAC total: total instance-related database buffers

Data source: V$SGA

Quality

Data buffer quality, calculated as follows:

100% – ((physicalreads – physicalreads_direct – physicalreads_directlob) / (sess_logicalreads – physicalreads_direct – physicalreads_directlob))

Non-RAC or RAC detail: data buffer quality of the current instance

RAC total: average of quality for all instance-related data buffer

Data source: V$SYSSTAT

Logical reads

Number of logical read operations

·        Non-RAC or RAC detail: logical reads of the current instance

·        RAC total: total logical read operations for all instances

Data source: V$SYSSTAT

Physical reads

Number of physical read operations

·        Non-RAC or RAC detail: physical reads of the current instance

·        RAC total: total physical read for all instances

Data source: V$SYSSTAT

Physical writes

Number of physical write operations

·        Non-RAC or RAC detail: physical writes of the current instance

·        RAC total: total physical write operations for all instances

Data source: V$SYSSTAT

Buffer busy waits

Number of buffer busy wait situations

·        Non-RAC or RAC detail: total waitstat counters of the current instance

·        RAC total: total waitstat counters for all instances

Data source: V$WAITSTAT

Buffer wait times (s)

Sum of buffer busy wait times

·        Non-RAC or RAC detail: sum of wait times for all wait counters of the current instance

·        RAC total: sum of wait times for all wait counters for all instances

Data source: V$WAITSTAT

Field

Description

Size (kB)

Shared pool size in KB

·        Non-RAC or RAC detail: shared pool size of the current instance

·        RAC total: total shared pool size for all instances

Data source: V$SGA_DYNAMIC_COMPONENTS

DD-cache quality (%)

Data dictionary cache quality as percentage, calculated as follows:

100% – (totalget_misses / totalgets)

·        Non-RAC or RAC detail: data buffer quality of the current instance

·        RAC total: average cache quality for all instances

Data source: V$ROWCACHE

SQL area getratio (%)

Ratio of gethits to gets as a percentage, calculated as follows:

sum (gethits) / sum (gets) x 100

·        Non-RAC or RAC detail: get ratio of the current instance

·        RAC total: average of all instance-related get ratios

Data source: V$LIBRARYCACHE

SQL area pinratio (%)

Ratio of pinhits to pins as a percentage, calculated as follows:

sum (pinhits) / sum (pins) x 100

·        Non-RAC or RAC detail: pin ratio of the current instance

·        RAC total: average of all instance-related pin ratios

Data source: V$LIBRARYCACHE

SQLA Reloads/pins (%)

Ratio of reloads to pins as a percentage, calculated as follows:

sum (reloads) / sum (pins) x 100

·        Non-RAC or RAC detail: reloads per pin ratio of the current instance

·        RAC total: average of all instance-related pin ratios

Data source: V$LIBRARYCACHE

Field

Description

Size (kB)

Size of the redo log buffer in KB

·        Non-RAC or RAC detail: redo log buffer size of the current instance

·        RAC total: total instance-related redo log buffer sizes

Data source: V$SGA

Entries

Number of redo log buffer entries

·        Non-RAC or RAC detail: redo log buffer entries of the current instance

·        RAC total: sum of all instance-related redo log buffer entries

Data source: V$SYSSTAT

Allocation retries

Number of redo buffer allocation retries

·        Non-RAC or RAC detail: allocation retries of the current instance

·        RAC total: total instance-related log buffer allocation retries

Data source: V$SYSSTAT

Alloc fault rate (%)

Redo buffer allocation retries as a percentage of redo entries

·        Non-RAC or RAC detail: allocation fault rate of the current instance

·        RAC total: average of all instance-related allocation fault rates

Data source: V$SYSSTAT

Redo log wait (s)

Redo log wait in seconds

·        Non-RAC or RAC detail: Redo log wait time of the current instance

·        RAC total: sum of instance-related redo log wait times

Data source: V$SYSSTAT

Log files (in use)

Number of active log files

·        Non-RAC or RAC detail: active log files for the current instance

·        RAC total: total active log files

The figure in brackets refers to the number of active log files in use.

Data source: V$LOGFILE

Field

Description

User calls

Number of user calls

·        Non-RAC or RAC detail: user calls for the current instance

·        RAC total: total user calls for all instances

Data source: V$SYSSTAT

User commits

Number of user commits

·        Non-RAC or RAC detail: user commits for the current instance

·        RAC total: total user commits for all instances

Data source: V$SYSSTAT

User rollbacks

Number of user rollbacks

·        Non-RAC or RAC detail: user rollbacks for the current instance

·        RAC total: total user rollbacks for all instances

Data source: V$SYSSTAT

Field

Description

Busy wait time (s)

Busy wait time in seconds, calculated as the sum of the time waited for all non-idle events.

·        Non-RAC or RAC detail: busy wait time for the current instance

·        RAC total: total instance-related busy wait times

Data source: V$SESSION_EVENT

CPU time session (s)

CPU time session in seconds, calculated as sum of CPU time used by this session

·        Non-RAC or RAC detail: total CPU time for the current instance

·        RAC total: total CPU time for all instances

Data source: V$SYSSTAT

Time/User call (ms)

Time for each user call in milliseconds, calculated as follows:

(busy wait time + CPU time) / user calls

·        Non-RAC or RAC detail: time for the current instance

·        RAC total: average time for all instances

Data source: V$SESSION_EVENT and V$SYSSTAT

Sessions busy (%)

Busy sessions as a percentage, calculated as follows:

(busy wait time + CPU time) / total wait time

·        Non-RAC or RAC detail: percentage for the current instance

·        RAC total: average percentage for all instances

Data source: V$SESSION_EVENT and V$SYSSTAT

CPU usage (%)

CPU usage as a percentage, calculated as follows:

CPU time / (elapsed time x CPU count)

·        Non-RAC or RAC detail: percentage for the current instance

·        RAC total: average percentage for all instances

Data source: V$SYSSTAT, V$INSTANCE, and V$PARAMETER

Number of CPUs

Number of CPUs

·        Non-RAC or RAC detail: CPUs for the current instance

·        RAC total: total CPUs for all instances

Data source: V$PARAMETER

Field

Description

Redo writes

Number of redo log writes

·        Non-RAC or RAC detail: redo log writes for the current instance

·        RAC total: total redo log writes for all instances

Data source: V$SYSSTAT

OS blocks written

Number of operating system redo blocks written

·        Non-RAC or RAC detail: redo blocks written for the current instance

·        RAC total: sum of written redo blocks for all instances

Data source: V$SYSSTAT

Latching time (s)

Redo writer latching time in seconds

Non-RAC or RAC detail: redo writer latching time for the current instance

RAC total: total latching time for all instances

Data source: V$SYSSTAT

Redo write time (s)

Redo write time in seconds

·        Non-RAC or RAC detail: redo write time for the current instance

·        RAC total: total redo write time for all instances

Data source: V$SYSSTAT

MB written

Number of MB written

·        Non-RAC or RAC detail: redo log data written for the current instance

·        RAC total: total redo log data written for all instances

Data source: V$SYSSTAT

Field

Description

Short table scans

Number of short table scans

·        Non-RAC or RAC detail: short table scans for the current instance

·        RAC total: total short table scans for all instances

Data source: V$SYSSTAT

Long table scans

Number of long table scans

·        Non-RAC or RAC detail: long table scans for the current instance

·        RAC total: total long table scans for all instances

Data source: V$SYSSTAT

Table fetch by rowid

Number of table fetches by row ID

·        Non-RAC or RAC detail: table fetches by row ID for the current instance

·        RAC total: total table fetches by row ID for all instances

Data source: V$SYSSTAT

Fetch by contin. row

Number of fetches by continued row

·        Non-RAC or RAC detail: table fetches by continued row for the current instance

·        RAC total: total table fetches by continued row for all instances

Data source: V$SYSSTAT

Field

Description

Sorts (memory)

Number of sorts in memory

·        Non-RAC or RAC detail: sorts in memory for the current instance

·        RAC total: total sorts in memory for all instances

Data source: V$SYSSTAT

Sorts (disk)

Number of sorts in disk

·        Non-RAC or RAC detail: sorts on disk for the current instance

·        RAC total: total sorts on disk for all instances

Data source: V$SYSSTAT

Sorts (rows)

Number of sorted rows

·        Non-RAC or RAC detail: sorted rows in memory for the current instance

·        RAC total: total rows for all instances

Data source: V$SYSSTAT

WA exec. optim. mode

Number of work area executions in optimal mode

·        Non-RAC or RAC detail: work area executions in optimal mode for the current instance

·        RAC total: total work area executions in optimal mode for all instances

Data source: V$SYSSTAT

WA exec. one pass m.

Number of work area executions in one-pass mode

·        Non-RAC or RAC detail: work area executions in one-pass mode for the current instance

·        RAC total: total work area executions in one-pass mode for all instances

Data source: V$SYSSTAT

WA exec. multipass m.

Number of work area executions below the one-pass memory requirement

·        Non-RAC or RAC detail: work area executions in multipass mode for the current instance

·        RAC total: total work area executions in multipass mode for all instances

Data source: V$SYSSTAT

Field

Description

Soft parse ratio

Soft parse ratio is calculated as follows:

1 – (parse count hard / parse count total)

This shows whether there are many hard parses on the system. The ratio should be compared to the raw statistics to ensure accuracy. For example a soft parse ratio of 0.2 typically indicates a high hard parse rate. However, if the total number of parses is low, you can disregard the ratio.

·        Non-RAC or RAC detail: ratio of the current instance

·        RAC total: average ratio for all instances

Data source: V$SYSSTAT

In-memory sort ratio

In-memory sort ratio is calculated as follows:

sorts in memory / (sorts in memory + sorts on disk)

This shows the proportion of sorts that are performed in memory. Optimally, in an operational online transaction processing (OLTP) system, most sorts are small and can be performed solely as in-memory sorts.

·        Non-RAC or RAC detail: ratio of the current instance

·        RAC total: average ratio for all instances

Source: V$SYSSTAT

Parse to exec. ratio

Parse to execute ratio is calculated as follows:

1 – (parse count total / execute count)

In an operational environment, optimally a SQL statement should be parsed once and executed many times. Therefore an ideal value is close to 1.

·        Non-RAC or RAC detail: ratio of the current instance

·        RAC total: average ratio of all instances

Source: V$SYSSTAT

Parse CPU to total

Parse-CPU-to-total ratio is calculated as follows:

1 – (parse time CPU / CPU used by this session)

This shows how much of the total CPU time used was spent on activities other than parsing. When this ratio is low, the system is performing too many parses.

·        Non-RAC or RAC detail: ratio of the current instance

·        RAC total: average ratio of all instances

Source: V$SYSSTAT

PTime CPU / PT elps

Parse time CPU / parse time elapsed ratio is calculated as follows:

parse time CPU / parse time elapsed

This can often indicate latch contention. The ratio indicates whether the time spent parsing is allocated to CPU cycles (that is, productive work) or whether the time spent parsing was not spent on CPU cycles. Time spent parsing not on CPU cycles usually indicates that the time was spent sleeping due to latch contention.

·        Non-RAC or RAC detail: ratio of the current instance

·        RAC total: average ratio of all instances

Source: V$SYSSTAT