This screen provides summary I/O information for all processes
activated to collect global statistics using the Process
Monitoring facility.
The processes displayed on this screen have previously activated
their global statistics collection. Process global statistic
collection can be either implicitly activated by the database
monitor, or explicitly activated by the RMU Show Statistic
utility.
This screen provides the following information:
o Process.ID
The process ID for the current process, assigned by the
operating system, and the stream ID, assigned by the database.
If "G" is appended to the process ID, the process had been
activated for global statistics collection; this is the normal
case. Server processes will be designated with the "s" tag.
o Sync.Reads
This field gives the number of synchronous read QIOs (queued
I/O requests) issued to the database storage area for
single-file and multifile databases and snapshot files.
This operation reads database pages synchronously from the
database.
o SyncWrites
This field gives the number of synchronous write QIOs (queued
I/O requests) issued to the database storage area for single-
file and multifile databases (.RDA) and snapshot files (.SNP).
This operation writes modified database pages synchronously
back to the database.
o Read.Stall
This field gives the time in hundredths of a second spent
reading database pages from the database rootfile (.RDB),
storage area (.RDA) files and snapshot (.SNP) files. An
excessively high number often indicates disk contention that
might be alleviated by moving some files to other disks.
This statistic field includes both synchronous and
asynchronous I/O read stall durations.
o WriteStall
This field gives the time in hundredths of a second spent
writing database pages to the database rootfile (.RDB),
storage area (.RDA) and snapshot (.SNP) files. An excessively
high number often indicates disk contention that might be
alleviated by moving some files to other disks.
This statistic field includes both synchronous and
asynchronous I/O read stall durations.
o AsyncReads
This field gives the number of asynchronous read QIOs (queued
I/O requests) issued to the database storage area for single-
file and multifile databases (.RDA) and snapshot (.SNP) files.
This operation reads database pages asynchronously from the
database.
o AsyncWrits
This field gives the number of asynchronous write QIOs (queued
I/O requests) issued to the database storage area for single-
file and multifile databases (.RDA) and snapshot files (.SNP).
This operation writes modified database pages asynchronously
back to the database.