How to Increase Memory Allocation for a Redis Instance on cPanel

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Redis memory usage counts toward your account’s total memory limit.

So if your LVE memory limit is:

• 1GB total, and you set Redis to 1024MB, you risk:
  • Hitting the limit
  • Causing slowdowns
  • Getting processes killed (including Redis or PHP)
  
  

Safe Approach

Keep Redis within 25%–50% of your LVE memory

Examples:

• LVE = 1GB → Redis: 256MB–512MB max
• LVE = 2GB → Redis: 512MB–1GB
• LVE = 4GB → Redis: 1GB–2GB

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This applies only to servers on the new infrastructure (domains ending in .mysecurecloudhost.com or .stableserver.com).

Step 1: Access Redis in cPanel

1. Log in to your cPanel account.
2. Navigate to cPanel → Redis.
3. Ensure your Redis instance is running:
   • If it is not running, click Start Redis Server.

Step 2: Connect to the Redis Instance

To modify Redis configuration, you’ll need to access it via the command line. Use the redis-cli tool with your instance’s port and password. For example:

redis-cli -p 41435 -a Pass1234

Once connected, you will see a prompt similar to:

127.0.0.1:41435>

Step 3: Set the Maximum Memory Limit

To increase the memory allocation, run:

CONFIG SET maxmemory 1024mb

This example sets the limit to 1024 MB (1 GB). Adjust the value as needed for your use case.

Step 4: Make the Change Persistent

By default, configuration changes are temporary. To save them permanently, run:

CONFIG REWRITE

This ensures the new memory limit persists after restarts.

Step 5: Verify the Configuration

To confirm the new memory allocation, run:

CONFIG GET maxmemory

You should see output similar to:

1) "maxmemory"
2) "1073741824"

The value is shown in bytes (in this case, 1024 MB = 1073741824 bytes).

Restart the Redis server and flush its database.