Knowledgebase

Database workloads have different resource priorities than typical web hosting — RAM and disk I/O speed usually matter far more than raw CPU count. This guide helps you size a VPS correctly for MySQL, PostgreSQL, MongoDB, or Redis.

RAM: The Most Important Resource

Databases perform best when frequently accessed data fits in memory (via the buffer pool/cache), avoiding slower disk reads. As a starting guideline:

Storage: NVMe Over Standard SSD

Databases perform many small, frequent read/write operations. NVMe storage's significantly higher IOPS (input/output operations per second) compared to standard SSD directly translates into faster query response times under real load.

CPU: Matters Less Than Expected

Unless you're running heavy analytical queries or aggregations, most database workloads are I/O and memory bound rather than CPU bound. 2–4 vCPUs is sufficient for many small-to-medium applications.

Dedicated Database VPS vs Combined with Application

Signs Your Database Needs More Resources

• Slow query log filling up with previously fast queries — see How to Tune MySQL/MariaDB Performance for a VPS
• High disk I/O wait time in iostat
• Buffer pool hit ratio dropping (frequent disk reads instead of memory reads)
• Connection timeouts under normal (not peak) load

Checking Current Database Size

MySQL/MariaDB:

SELECT table_schema AS "Database", 
  ROUND(SUM(data_length + index_length) / 1024 / 1024, 2) AS "Size (MB)" 
  FROM information_schema.tables GROUP BY table_schema;

PostgreSQL:

SELECT pg_size_pretty(pg_database_size('myapp'));

When to Separate the Database onto Its Own VPS

Consider a dedicated database server once your application VPS shows resource contention between the web server and database under load, or once you need independent scaling/backup schedules for each.

FAQ

Should I always use a separate VPS for my database?
Not necessarily for small projects — combining app and database on one VPS is fine until you observe actual resource contention; separating early adds operational complexity without guaranteed benefit for low-traffic workloads.

Related Articles

• How to Choose the Right VPS Plan for Your Workload
• How to Tune MySQL/MariaDB Performance for a VPS
• MySQL vs PostgreSQL vs MongoDB vs Redis: Which Database Should You Use?