- Release Notes and Announcements
- User Guide
- Product Introduction
- Purchase Guide
- Getting Started
- Operation Guide
- Access Management
- Instance Management
- Node Management
- Node Overview
- Viewing Node Information
- Adjusting Mongod Node Specification
- Adding Secondary Node
- Deleting Secondary Node
- Adding Read-Only Node
- Adjusting Shard Quantity
- Adjusting Mongos Node Specification
- Adding Mongos Node
- Enabling Mongos Access Address
- Promoting Secondary Node to Primary Node
- Restarting a Node
- Version Upgrade
- Network Configuration
- Monitoring
- Backup and Rollback
- Data Security
- SSL Authentication
- Database Management
- Multi-AZ Deployment
- Disaster Recovery/Read-Only Instances
- Recycle Bin
- Task Management
- Performance Optimization
- Data Migration Guide
- Creating a DTS Migration Task
- Migration Overview
- Supported Capabilities
- User Guide
- Migration Operation Guide
- Fix for Verification Failure
- MongoDB Connection Check
- Database/Table Content Conflict Check
- Source Database Node Role Check
- Oplog Check
- Source/Target Database Account Permission Check
- Database Version Check
- Database Capacity Check
- Target Database Load Check
- ShardKey Check
- Source Database Balancer Check
- Time Series Collection Verification
- Compression Algorithm Verification
- Consistency Check After Migration
- Creating MongoDB Data Subscription
- Creating a DTS Migration Task
- Practical Tutorial
- Optimizing Indexes to Break Through Read/Write Performance Bottlenecks
- Troubleshooting Mongos Load Imbalance in Sharded Cluster
- Considerations for Using Shard Clusters
- Sample of Reading and Writing Data in MongoDB Instance
- Methods for Importing and Exporting Data Based on CVM Connected with MongoDB
- What to Do for Errors of Repeated Instance Creation and Deletion of Databases with the Same Names?
- Troubleshooting MongoDB Connection Failures
- Performance Fine-Tuning
- Ops and Development Guide
- Troubleshooting
- API Documentation
- History
- Introduction
- API Category
- Making API Requests
- Instance APIs
- RenameInstance
- OfflineIsolatedDBInstance
- ModifyDBInstanceSpec
- IsolateDBInstance
- DescribeSpecInfo
- DescribeDBInstances
- DescribeClientConnections
- CreateDBInstanceHour
- AssignProject
- RenewDBInstances
- DescribeSlowLogs
- DescribeSlowLogPatterns
- InquirePriceRenewDBInstances
- InquirePriceModifyDBInstanceSpec
- InquirePriceCreateDBInstances
- DescribeDBInstanceDeal
- DescribeSecurityGroup
- DescribeInstanceParams
- ModifyDBInstanceSecurityGroup
- ModifyDBInstanceNetworkAddress
- Backup APIs
- Account APIs
- Task APIs
- Other APIs
- Data Types
- Error Codes
- Instance Connection
- Product Performance
- FAQs
- Service Agreement
- Glossary
- Contact Us
- Release Notes and Announcements
- User Guide
- Product Introduction
- Purchase Guide
- Getting Started
- Operation Guide
- Access Management
- Instance Management
- Node Management
- Node Overview
- Viewing Node Information
- Adjusting Mongod Node Specification
- Adding Secondary Node
- Deleting Secondary Node
- Adding Read-Only Node
- Adjusting Shard Quantity
- Adjusting Mongos Node Specification
- Adding Mongos Node
- Enabling Mongos Access Address
- Promoting Secondary Node to Primary Node
- Restarting a Node
- Version Upgrade
- Network Configuration
- Monitoring
- Backup and Rollback
- Data Security
- SSL Authentication
- Database Management
- Multi-AZ Deployment
- Disaster Recovery/Read-Only Instances
- Recycle Bin
- Task Management
- Performance Optimization
- Data Migration Guide
- Creating a DTS Migration Task
- Migration Overview
- Supported Capabilities
- User Guide
- Migration Operation Guide
- Fix for Verification Failure
- MongoDB Connection Check
- Database/Table Content Conflict Check
- Source Database Node Role Check
- Oplog Check
- Source/Target Database Account Permission Check
- Database Version Check
- Database Capacity Check
- Target Database Load Check
- ShardKey Check
- Source Database Balancer Check
- Time Series Collection Verification
- Compression Algorithm Verification
- Consistency Check After Migration
- Creating MongoDB Data Subscription
- Creating a DTS Migration Task
- Practical Tutorial
- Optimizing Indexes to Break Through Read/Write Performance Bottlenecks
- Troubleshooting Mongos Load Imbalance in Sharded Cluster
- Considerations for Using Shard Clusters
- Sample of Reading and Writing Data in MongoDB Instance
- Methods for Importing and Exporting Data Based on CVM Connected with MongoDB
- What to Do for Errors of Repeated Instance Creation and Deletion of Databases with the Same Names?
- Troubleshooting MongoDB Connection Failures
- Performance Fine-Tuning
- Ops and Development Guide
- Troubleshooting
- API Documentation
- History
- Introduction
- API Category
- Making API Requests
- Instance APIs
- RenameInstance
- OfflineIsolatedDBInstance
- ModifyDBInstanceSpec
- IsolateDBInstance
- DescribeSpecInfo
- DescribeDBInstances
- DescribeClientConnections
- CreateDBInstanceHour
- AssignProject
- RenewDBInstances
- DescribeSlowLogs
- DescribeSlowLogPatterns
- InquirePriceRenewDBInstances
- InquirePriceModifyDBInstanceSpec
- InquirePriceCreateDBInstances
- DescribeDBInstanceDeal
- DescribeSecurityGroup
- DescribeInstanceParams
- ModifyDBInstanceSecurityGroup
- ModifyDBInstanceNetworkAddress
- Backup APIs
- Account APIs
- Task APIs
- Other APIs
- Data Types
- Error Codes
- Instance Connection
- Product Performance
- FAQs
- Service Agreement
- Glossary
- Contact Us
Overview
Oplog is an important component in MongoDB used to log the operations in the database. The oplog capacity should be at least 10% of the node capacity, as the oplog records all database operations, including insertions, updates, and deletions. If the oplog capacity is too small, the oplog may be overwritten, affecting the rollback feature of MongoDB. When you purchase an instance, the oplog capacity is 10% of the instance capacity by default and can be expanded to 90% of the instance capacity as needed; however, it cannot be shrunk currently.
Prerequisites
You have created a TencentDB for MongoDB instance. For more information, see Creating TencentDB for MongoDB Instance.
If your instance is pay-as-you-go, make sure that your Tencent Cloud account balance is sufficient.
The instance and its associated instances are in Running status and are not executing any tasks.
Directions
1. Log in to the TencentDB for MongoDB console.
2. In the MongoDB drop-down list on the left sidebar, select Replica Set Instance or Shard Instance. The directions for the two types of instances are similar.
3. Above the Instance List on the right, select the region.
4. In the instance list, find the target instance.
5. In the Oplog Info column, click View/Adjust.
6. In the Adjust Oplog pop-up window, confirm the instance information and evaluate the target oplog capacity based on the current capacity.
Note:
The Oplog capacity should be at least 10% of the node capacity. When the size of the Oplog file reaches its maximum capacity, MongoDB starts overwriting previous operation records from the beginning of the file. If the Oplog is too small, it can lead to rapid data overwrite, posing Ops risks.
Interface Parameters | Description |
Oplog retention duration | The time it takes for the Oplog storage to be filled. If the Oplog is not full, the retention duration is an estimate. |
Current total capacity | The storage capacity of the Oplog for each Mongod node. |
Capacity After Scale-out | Use the slider to set the Oplog capacity after scale-out. |
7. Click OK, and then in the left sidebar, choose Task Management. Wait for the task to complete the scale-out.
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