1.178 LOG_ARCHIVE_TRACE

LOG_ARCHIVE_TRACE enables and controls the generation of comprehensive trace information for log archiving and redo transport activity.

Property Description

Parameter type

Integer

Default value

0

Modifiable

ALTER SYSTEM

Modifiable in a PDB

No

Range of values

0, 1, 2, 4, 8, 16, 32, 64, 128, 256, 512, 1024, 2048, 4096, 8192, 16384, 32768

Basic

No

Oracle RAC

Multiple instances can have different values.

The additional tracing that is output when setting LOG_ARCHIVE_TRACE to a non-zero value can appear in trace files for an archive process, RFS process, LGWR process, SYNC process, ASYNC process, foreground process, MRP process, recovery process, log apply process, startup process, shutdown process, and other processes that use redo transport services.

Table 1-4 describes the valid LOG_ARCHIVE_TRACE values.

Table 1-4 LOG_ARCHIVE_TRACE Values

Value Description More Information

0

Disables archivelog tracing (this is the default)

1

High-level tracing

High-level tracing provides a small amount of tracing from most redo transport processes. When a value is specified that is not high-level (not 1), the high-level tracing for that value will be output to the trace file even if the high-level tracing has not been specifically requested. For example, if you set LOG_ARCHIVE_TRACE to 128, you will get all the trace messages pertaining to the FAL engine, including the high-level tracing from the FAL engine.

2

Tracks Data Guard interfaces

This tracing level is for the various Data Guard configuration parameters, the various Data Guard related SQL commands, the various Data Guard table accesses, and some Data Guard internal interfaces.

4

Tracks common redo transport services

This tracing level is for a number of common services provided by redo transport to various internal users (such as the RFS process, the LGWR process, and the ASYNC process). These include locking primitives, use of common VOS (Virtual Operating System) interfaces, task scheduling, process monitoring, control file access, and other miscellaneous common services.

8

Tracks database protection mode

16

Tracks disk and network I/O requests

32

Tracks redo transport destinations

64

Tracks redo transport archive engine

128

Tracks redo transport FAL (fetch archive log) engine

256

Tracks Physical, Logical, and Availability Machine clients of RFS process

512

Tracks redo transport of LGWR, SYNC, and ASYNC processes

1024

Tracks redo transport RFS process

2048

Tracks redo transport gap resolution

4096

Tracks real-time apply

8192

Tracks recovery process

16384

Tracks redo transport buffer management

32768

Tracks LogMiner dictionary

You can combine tracing levels by adding together the values of the desired tracing levels. For example, a setting of 3 will generate level 1 and level 2 trace output. You can set different values for the primary and standby database.

When this parameter is set to the default value of 0, Oracle will still generate appropriate alert and trace entries in response to error conditions. If you change the value of this parameter dynamically in an ALTER SYSTEM statement, the change takes effect immediately.

Many of the trace messages from redo transport processes include a routine name at the beginning of the trace message. The first part of the routine name specifies the module for that routine. Table 1-5 shows the tracing value used for each redo transport module. Note that the tracing value for transport modules can change from release to release.

Table 1-5 Tracing Values Used for Redo Transport Modules

Module Name Purpose Tracing Value

krsa

Locking primitives

4

krsb

Buffer management

16384

krsc

Crash recovery

64

krsd

Destination

32

krse

Archive engine

64

krsf

FAL engine

128

krsg

Gap resolution

2048

krsh

Helper

4

krsi

Input/output

16

krsj

Protection mode

8

krsk

Control file access

4

krsl

Log writer

512

krsm

MRP process

8192

krsn

Configuration

2

krso

Process monitor

4

krsp

Physical standby and Availability Machine RFS client

256

krsq

SQL commands

2

krsr

RFS process

1024

krst

Tables

2

krsu

Network I/O

16

krsv

VOS front end

4

krsw

ASYNC process

512

krsx

Internal interfaces

2