Progress Before-Image Log Activity Test

The Before Image file(s) stores information about every transaction which makes a change to the database. If the transaction is aborted / undone, this information will be read back from the BI file to restore original values of the database back into the database if necessary.

In addition when a database goes down unexpectedly, the crash recovery process reads back and undo any transaction that was not completed.

Target of the test : A Progress Database server

Agent deploying the test : An internal agent

Outputs of the test : One set of results for every Progress database server that is being monitored

Configurable parameters for the test
Parameter	Description
Test Period	How often should the test be executed
Host	The IP address of the Progress database server.
Port	The port number on which the database server is listening. By default, this is NULL.
Database Name	Specify the name of the Progress database instance that is to be monitored.
Username	In order to monitor a Progress database instance, a special database user account has to be created in every Progress database instance that requires monitoring. This special user needs to be granted a set of privileges. To know how to create the database user and grant the required privileges, refer to Pre-Requisites for monitoring the Progress database. Specify the name of such a user in this text box.
Password	The password of the specified Username.
Confirm Password	Confirm the password by retyping it here.

Measurements made by the test
Measurement	Description	Measurement Unit	Interpretation
Total writes	Indicates the total number of writes to the before-image file during the last measurement period.	Writes/Sec	The value of this measure includes the value of the BIW writes measure too.
BIW writes	Indicates the total number of writes performed by the Before-Image writer during the last measurement period.	Writes/Sec	The BIW is a background process that continually writes filled BI buffers to disk. Since writes to the BI file occur in the background, client and server processes rarely have to wait for a filled buffer to be written to disk. BIWs are optional, but highly recommended for improving I/O performance.
BIW write hit ratio	Indicates the ratio between the writes performed by the before-Image writer and the total writes to the Before image file during the last measurement period.	Percent
Buffer busy waits	Indicates the number of times Buffer Busy waits have occurred on the before image file when a block in the buffer cache was being held by the Before image writer during the last measurement period.	Number
Committed waits	Indicates the rate at which commit waits have occurred on the before image file when a block in the buffer cache was being held by the Before image writer during the last measurement period.	Records/sec
Log size	Indicates the current size of the before-image log file.	MB
Growth rate	Indicates the rate at which the size of the before-image log file had grown during the last measurement period.	MB/sec	A consistent increase in the value of this measure is a cause for concern, as it indicates a steady growth in before-image log file size.