Output Description

The first portion of the display describes reads and writes.

Reads and writes are tabulated in three categories: from disk, from buffers, and number of pages (read or written).

The first %cached field is a measure of the number of reads from buffers compared to reads from disk. The second %cached field is a measure of the number of writes to buffers compared to writes to disk.

The database server buffers information and writes to the disk in pages. For this reason, the number of disk writes displayed as dskwrits is usually less than the number of writes that an individual user executes:

dskreads

is the number of actual reads from disk.

pagreads

is the number of pages read.

bufreads

is the number of reads from shared memory.

%cached

is the percent of reads cached, calculated as follows:

100 * (bufreads - dskreads) / bufreads 

If bufreads exceeds the maximum integer (or long) value, its internal representation becomes a negative number, but the value appears as 0.0.

dskwrits

is the actual number of physical writes to disk. This number includes the writes for the physical and logical logs reported in onstat -l.

pagwrits

is the number of pages written.

bufwrits

is the number of writes to shared memory.

%cached

is the percent of writes cached, calculated as follows:

100 *(bufwrits - dskwrits) / bufwrits 

If dskwrits exceeds bufwrits, the value appears as 0.0.

The next portion of the -p display tabulates the number of times different ISAM calls were executed. The calls occur at the lowest level of operation and do not necessarily correspond one-to-one with SQL statement execution. A single query might generate multiple ISAM calls. These statistics are gathered across the database server and cannot be used to monitor activity on a single database unless only one database is active or only one database exists:

isamtot

is the total number of calls.

open

increments when a tblspace is opened.

start

increments the pointer within an index.

read

increments when the read function is called.

write

increments with each write call.

rewrite

increments when an update occurs.

delete

increments when a row is deleted.

commit

increments each time that an iscommit() call is made. No one-to-one correspondence exists between this value and the number of explicit COMMIT WORK statements that are executed.

rollbk

increments when a transaction is rolled back.

The third portion of the -p display tracks the number of times that a resource was requested when none was available:

ovlock

is the number of times that the database server attempted to exceed the maximum number of locks (specified as LOCKS in the ONCONFIG file).

ovuserthread

is the number of times that a user attempted to exceed the maximum number of user threads.

ovbuff

is the number of times that the database server could not find a free shared-memory buffer. When no buffers are free, the database server writes a dirty buffer to disk and then tries to find a free buffer.

usercpu

is the total user CPU time that all user threads use, expressed in seconds. This entry is updated every 15 seconds.

syscpu

is the total system CPU time that all user threads use, expressed in seconds. This entry is updated every 15 seconds.

numckpts

is the number of checkpoints since the boot time.

flushes

is the number of times that the buffer pool has been flushed to the disk.

The next portion of the -p display contains miscellaneous information, as follows:

bufwaits

increments each time that a user thread must wait for a buffer.

lokwaits

increments each time that a user thread must wait for a lock.

lockreqs

increments each time that a lock is requested.

deadlks

increments each time that a potential deadlock is detected and prevented.

dltouts

increments each time that the distributed deadlock time-out value is exceeded while a user thread is waiting for a lock.

ckpwaits

is the number of checkpoint waits.

compress

increments each time that a data page is compressed.

seqscans

increments for each sequential scan.

The last portion of the -p display contains the following information:

ixda-RA

is the count of read-aheads that go from index leaves to data pages.

idx-RA

is the count of read-aheads that traverse index leaves.

da-RA

is the count of data-path-only scans.

RA-pgsused

indicates the number of pages used that the database server read ahead. If this number is significantly less than the total number of pages read ahead, the read-ahead parameters might be set too high.

lchwaits

increments when a thread waits to gain access to a shared-memory resource.