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Oracle Redo Log Sizing - Exercise

Size redo logs for Oracle 23ai

Objective: Write a practical sizing plan for online redo logs and archived redo log capacity using modern Oracle best practices.

Current best practice context

In Oracle 23ai, redo log sizing is still relevant for DBA-managed databases (on-premises and co-managed cloud services). Installation tooling can provide defaults, but you still validate log switch frequency, ensure adequate redo log groups, and prevent archive destinations from filling. In Oracle Autonomous Database, redo log sizing is handled by the service.

Exercise scoring

This exercise is worth 12 points (3 points per response area). There are no “solutions” on this page. Your goal is to describe a defensible approach and how you would verify it after go-live.

Scenario

You are planning a new OLTP database. The vendor estimates about 1,000,000 row changes per day with an average change size of ~80 bytes. You have limited workload detail beyond that. Your backup strategy is nightly full backups, and you want to support roll-forward recovery between backups.

Instructions

Provide your plan in the text boxes below. Focus on redo log sizing and operational verification.

1. Online redo log sizing target
Include: target log switch cadence during peak hours, initial log size proposal, and what you would change if switches are too frequent.

2. Redo log group design
Include: number of groups, multiplexing (members per group), placement guidance (ASM disk groups / separate failure domains), and why.

3. Archived redo log capacity plan
Include: how much archive log capacity you want available, what retention window it supports, and how you would prevent a “destination full” outage (for example, FRA sizing plus backup-and-delete strategy).

4. Verification queries and monitoring steps
Include: which views/logs you would check (for example V$LOG, V$LOGHIST, alert log, AWR) and what signals would indicate redo I/O contention.

Submitting your exercise

After completing all four response areas, click Submit. Your text will be posted to the exercise result page for review.