Cloud SQL disk usage issue

Google Cloud Database
1

Hi all,

I’m having an issue where there was a disk usage spike under “Other” category found in metric explorer.

The spike keep increasing and dropped. This behavior happening in half an hour time.

1000010757.jpg
1000010757.jpg800×735 27.5 KB

Would like to know what is this “Other” containing

MySQL 5.7

2

The “Other” category in disk usage metrics for MySQL on Cloud SQL encompasses several components not directly attributed to your database data files. This includes:

  • Temporary Files: Generated by MySQL for sorting, large transactions, or complex queries that exceed the available memory.
  • Internal Data Structures: Utilized by MySQL for its internal operations. These can grow in certain situations depending on database activity.
  • Logs: Error logs, slow query logs, general query logs (if enabled), and potentially other logs depending on your configuration.
  • Data Fragments from Deleted Tables/Rows (Potentially): Sometimes, even after deleting data, the space might not be immediately reclaimed.

Possible Causes of Disk Usage Spikes in “Other”

  • Unoptimized Queries: Inefficient queries can lead to excessive temporary table creation, causing disk usage spikes. Use the slow query log and Cloud SQL Query Insights to identify and optimize.
  • Large Transactions: Significant insert, update, or delete operations within a single transaction can temporarily consume more disk space.
  • BLOBs and Large Data Types: Storing large binary objects (BLOBs) or other oversized data types can contribute to “Other” disk usage.
  • Logging: Extensive logging without proper rotation can lead to increased disk usage. Review your log settings in the Cloud SQL console.

Investigating Disk Usage Spikes

  1. Examine Metric Explorer: Analyze the disk usage graph in the Cloud SQL console. Try to correlate spikes with specific timeframes or events.
  2. Review Logs: Check your MySQL error log and slow query log, focusing on the period during the spike.
  3. Query Performance Analysis: Use the following tools and techniques:
    • EXPLAIN statements to analyze query execution plans
    • Cloud SQL Query Insights

Additional Considerations

  • Automatic Storage Increase: Disable automatic storage increase unless you absolutely need it. This can lead to unexpected costs.
  • Log Management: Configure log rotation and archiving strategies through settings in the Cloud SQL console.

Please Note: Due to Cloud SQL being a managed service, you won’t have direct access to the file system. Your primary tools are Metric Explorer, logs, and query analysis tools provided by Google Cloud.