Oracle 19c Performance Tuning

Oracle High CPU Usage: Causes and Fix in 19c

 Chetan Yadav — Senior Oracle DBA ⏱ 10 min read  Troubleshoot Guide

How to Read Oracle AWR Report in 19c: DBA Guide

How to Read an Oracle AWR Report in 19c

A practical reading order from real production incidents, not a feature tour.

Oracle 19c Performance Tuning AWR Report Production DBA

An AWR report is a snapshot of where your instance spent its time. Reading it in the right order is half the battle.

02:14. The on-call page hit: checkout API p95 had jumped from 180 ms to 4.2 seconds. No errors. No node eviction. No failover. Just a database that had quietly gone slow under a normal load. The first artifact I pulled was a one-hour AWR report, and within four minutes it pointed straight at the cause.

If you have ever stared at a 30-page AWR report and not known where to look first, this guide is for you. Knowing how to read an Oracle AWR report in 19c is not about understanding every section. It is about reading a handful of sections in the right order so you can go from "the database is slow" to "this SQL on this object is the problem" in minutes. That is exactly what I did at 02:14, and it is the workflow I will walk you through here.

AWR (Automatic Workload Repository) takes regular snapshots of performance statistics and stores them in the SYSAUX tablespace. A report compares two snapshots and shows you the delta: what the instance did, where it waited, and which statements drove the load. The trick is to stop reading top to bottom and start reading by importance.

Who this guide is for

Junior and mid-level DBAs who can generate an AWR report but freeze when it comes to interpreting it, and senior engineers who want a tighter triage checklist for incidents. Examples use Oracle 19c, but the reading order applies to 12c and 18c as well.

Standby Redo Logs Not Applying Oracle Data Guard Fix

Standby Redo Logs Not Applying in Oracle Data Guard: Complete Fix Guide

MRP process troubleshooting, SRL configuration, apply lag resolution, and parallel apply tuning from 15 years of production Oracle environments.

Oracle 19c / 21c Data Guard Troubleshooting Senior DBA Production Guide

Who This Is For: Junior to Senior Oracle DBAs managing Oracle 19c or 21c Data Guard environments who are troubleshooting standby redo logs not applying, MRP process failures, or unexplained apply lag. Freshers studying for Oracle certification will also benefit from the architecture walkthrough.

It was 2:41 AM. PagerDuty fires. The on-call message reads: "Data Guard apply lag 38 minutes and climbing." I SSH into the standby. ORA-16766 stares back at me from the alert log. A quick check of V$MANAGED_STANDBY confirms it -- MRP0 is gone. No standby redo logs are applying. The business had a 4-hour RPO commitment. We had maybe 90 minutes before the DBA team had a very uncomfortable conversation with the CTO.

Standby redo logs not applying in Oracle Data Guard is one of the highest-stress incidents a production DBA faces. It is also one of the most fixable -- if you know the exact diagnostic tree. In this post I am going to walk through every root cause I have encountered across 15 years of Oracle production work, the precise SQL to diagnose each one, and the fix you run to get apply moving again.

Environment Reference: Oracle 19c (19.19 RU), 2-node RAC primary + single-node physical standby, SYNC transport, 6 TB database, peak 12,000 TPS. All SQL verified in this environment. Steps also apply to Oracle 21c and Oracle 23ai Data Guard configurations.

Fresher Resume Format for Tech Jobs 2026: ATS Tips

Fresher Resume Format for Tech Jobs 2026

What ATS filters, what recruiters actually read, and the exact structure that gets callbacks in India's tech hiring market

May 21, 2026 Chetan Yadav 9 min read Freshers Resume Writing

Who this is for: Final-year students, recent graduates, and career switchers applying to tech companies in India and globally in 2026. If you have sent 50+ applications and heard nothing back, the problem is almost certainly your resume format and ATS compatibility, not your skills. After reading this post you will have: the correct fresher resume structure, a copy-ready template, the five most common mistakes to fix today, and an action checklist you can execute this week.

MRP Process Not Running in Data Guard: Fix in Oracle 19c

MRP Process Not Running in Data Guard? Fix It Step-by-Step (Oracle 19c)

5 Root Causes, DGMGRL Diagnosis and Exact Fix Commands for Every Scenario

📅 April 2026

👤 Chetan Yadav, Senior Oracle & Cloud DBA, Oracle ACE Apprentice

⏱️ 12,14 min read

⏱️ Estimated Reading Time: 12,14 minutes

MRP Not Running, ORA-16766, DGMGRL Fix, SRL Creation, Broker State, Auto-Start Trigger, Oracle 19c

⚙️ Environment Referenced in This Article

Oracle Database: 19.18.0.0.0 Enterprise Edition  •  Primary: 2-Node RAC, 4.8 TB OLTP, 2,800 TPS
Standby: Physical Standby with Active Data Guard enabled
Protection Mode: Maximum Availability (SYNC/AFFIRM)  •  Broker: Data Guard Broker enabled

The monitoring alert arrived at 2:48 AM: "Standby apply lag crossing 90 minutes." I connected to DGMGRL immediately. SHOW CONFIGURATION confirmed it: the MRP process was not running on the standby. Every transaction committed on the primary for the past 90 minutes was sitting unprocessed in Standby Redo Logs, and the gap was growing by the second.

In my 15 years managing Oracle production environments, a stopped MRP process is one of the most common Data Guard incidents I have resolved. It is not complicated once you know which of the five root causes you are dealing with. The problem is that each cause has a completely different fix, and applying the wrong one wastes critical time.

This guide gives you the exact decision path, the diagnostic commands to identify your specific cause, and the precise fix for each scenario. In most cases the MRP process not running in Data Guard is resolved in under 5 minutes.

ORA-16766 Error in Oracle Data Guard: Causes and Fix (19c Guide)

ORA-16766 Error in Oracle Data Guard: Causes and Fix (Oracle 19c Guide)

Redo Apply Service Not Running, How to Diagnose and Restart MRP in Under 5 Minutes

📅 4 May 2026

👤 Chetan Yadav, Senior Oracle & Cloud DBA

⏱️ 10-12 min read

⏱️ Estimated Reading Time: 10-12 minutes

ORA-16766, MRP Not Running, DGMGRL Diagnosis, MRP Restart, Standby Apply Fix, Oracle 19c

ORA-16766

Full Error: ORA-16766: Redo Apply is stopped

This error appears in DGMGRL SHOW CONFIGURATION output against the standby database. It means the Managed Recovery Process (MRP) on the standby has stopped and redo is no longer being applied. The standby is diverging from the primary with every passing second.

It was 3:22 AM. The monitoring alert fired: "Data Guard configuration warning — ORA-16766 on standby." Apply lag had jumped from zero to 47 minutes in under an hour. The standby database was alive, connected, receiving redo, but not applying any of it.

ORA-16766 is one of the most common Oracle Data Guard errors in production Oracle 19c environments. It always means the same thing: the MRP process on the standby has stopped. But the reasons it stops, and the correct fix for each reason, are completely different.

This guide covers every root cause of ORA-16766 in Oracle 19c, the exact DGMGRL and SQL commands to diagnose it, and the step-by-step fix commands for each scenario. Most ORA-16766 errors are resolved in under 5 minutes once you know which cause you are dealing with.

Why You're Not Getting Interview Calls: Blind Applications vs Targeted Strategy

Why You're Not Getting Interview Calls in 2026: Blind Applications vs Targeted Strategy

100 Applications. 0 Responses. Here Is Exactly Why, and How to Fix It.

📅30 April 2026

👤 Chetan Yadav, Senior Oracle & Cloud DBA

⏱️ 12 - 14 min read

⏱️ Estimated Reading Time: 12,14 minutes

Blind Applications, ATS Failures, No Referral Strategy, Quality vs Quantity, Targeted Job Search 2026

🎯 Who This Guide Is For

Final year students sending applications and hearing nothing back. Freshers who have applied to 80,200 jobs over several months with 0,2 responses. Anyone who has been told "just keep applying" without being told why their applications are failing and what to do differently.

If you are not getting interview calls despite sending dozens of applications, the problem is almost never your skills or your degree. Freshers not getting interview calls in 2026 is an epidemic, and the root cause is almost always the same: blind, untargeted applications that fail before any human ever reads them.

A student messaged me last month: "I have applied to 140 jobs in the last 3 months. I have received 2 responses and both were rejections. I have a decent GPA, a relevant degree, and I have been doing everything right. What am I missing?"

The answer was not what she expected. She was not missing skills. She was not missing certifications. She was applying to jobs the wrong way. Every application was a copy-paste of the same generic resume. No keyword matching. No company research. No follow-up. No referral outreach.

She was doing everything she had been told to do, and none of it was working because the advice she had been given was wrong. This guide explains the real reasons, and the exact targeted job search strategy that actually produces interview calls.