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Database Server Metrics

The scope for these metrics is always the named database server, which means the database server as a whole, rather than a component of the database server or disk space.

Metric Name Description
CPU System Time System time, as defined by the platform vendor
CPU User Time User time, as defined by the platform vendor
Percent Cached (Read) Percentage of all read operations that are read from the buffer cache without requiring a disk read, calculated as follows:
100 * ((buffer_reads — disk_reads) /
    (buffer_reads)) 
Percent Cached (Write) Percentage of all write operations that are buffer writes, calculated as follows:
100 * ((buffer_writes — disk_writes) /
    (buffer_writes)) 
Disk Reads Total number of read operations from disk
Disk Writes Total number of write operations to disk
Page Reads Number of pages read from disk
Page Writes Number of pages transferred to disk
Buffer Reads Number of reads from the buffer cache
Buffer Writes Number of writes to the buffer cache
Calls Number of calls received at the database server
Reads Number of read calls received at the database server
Writes Number of write calls received at the database server
Rewrites Number of rewrite calls received at the database server
Deletes Number of delete calls received at the database server
Commits Number of commit calls received at the database server
Rollbacks Number of rollback calls received at the database server
Table Overflows Number of times that the tblspace table was unavailable (overflowed)
Lock Overflows Number of times that the lock table was unavailable (overflowed)
User Overflows Number of times that the user table was unavailable (overflowed)
Checkpoints Number of checkpoints written since database server shared memory was initialized
Buffer Waits Number of times that a thread waited to access a buffer
Lock Waits Number of times that a thread waited for a lock
Lock Requests Number of times that a lock was requested
Deadlocks Number of deadlocks detected
Deadlock Timeouts Number of deadlock timeouts that occurred (Deadlock timeouts involve distributed transactions.)
Checkpoint Waits Number of checkpoint waits; in other words, the number of times that threads have waited for a checkpoint to complete
Index to Data Pages Read-aheads Number of read-ahead operations for index keys
Index Leaves
Read-aheads
Number of read-ahead operations for index leaf nodes
Data-path-only
Read-aheads
Number of read-ahead operations for data pages
Latch Requests Number of latch requests
Network Reads Number of ASF messages read
Network Writes Number of ASF messages written
Memory Allocated Amount of database server virtual-address space in kilobytes
Memory Used Amount of database server shared memory in kilobytes
Temp Space Used Amount of shared memory allocated for temporary tables in kilobytes
PDQ Calls The total number of parallel-processing actions that the database server performed
DSS Memory Amount of memory currently in use for decision-support queries
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