What is ScyllaDB DiskFull

Resolving Disk Full Issues in ScyllaDB

Introduction to ScyllaDB

ScyllaDB is a high-performance, distributed NoSQL database designed for real-time big data applications. It is compatible with Apache Cassandra and offers low-latency and high-throughput capabilities. ScyllaDB is used for applications that require high availability and scalability.

Identifying the Symptom

One common issue encountered in ScyllaDB is the 'DiskFull' error. This issue arises when the disk space allocated for ScyllaDB is exhausted. Users may notice write operations failing, and there is a risk of potential data loss if the issue is not addressed promptly.

Observing the Error

When the disk is full, you may encounter error messages in the logs indicating that write operations cannot be completed. Monitoring tools may also alert you to low disk space conditions.

Understanding the DiskFull Issue

The 'DiskFull' issue occurs when the storage capacity of the disk used by ScyllaDB is completely utilized. This prevents any further write operations, which can lead to application downtime and data inconsistency.

Root Cause Analysis

The primary cause of this issue is insufficient disk space to accommodate the data being written to the database. This can result from unexpected data growth, inadequate initial disk provisioning, or lack of regular maintenance to clear unnecessary data.

Steps to Resolve DiskFull Issue

To resolve the 'DiskFull' issue, you can take several actions to free up space or increase storage capacity.

Free Up Disk Space

Identify and delete unnecessary data or old backups that are no longer needed. Use the nodetool cleanup command to remove obsolete data from nodes after a topology change. Regularly run nodetool compact to reclaim space by merging SSTables.

Increase Disk Capacity

Consider adding more disks to your existing setup to increase storage capacity. Resize existing disks if your infrastructure supports dynamic resizing.

Add Additional Storage

Scale out by adding more nodes to your ScyllaDB cluster, which will distribute the data and reduce the load on individual disks. Ensure that new nodes have adequate disk space to handle future data growth.

Conclusion

Addressing the 'DiskFull' issue in ScyllaDB is crucial to maintaining database performance and preventing data loss. By regularly monitoring disk usage and implementing the steps outlined above, you can ensure that your ScyllaDB cluster remains healthy and efficient.

For more information on managing disk space in ScyllaDB, visit the ScyllaDB Maintenance Tasks page.