How to change the blockchain fetching batch size?

Video guide

Introduction

The default batch size is 100, but this can be changed by using the extra command --batch-size=xx.

You need to this to the command line as an extra flag or if you are using Docker, modify the docker-compose.yml with:

subquery-node:
    image: onfinality/subql-node:latest
    depends_on:
      - "postgres"
    restart: always
    environment:
      DB_USER: postgres
      DB_PASS: postgres
      DB_DATABASE: postgres
      DB_HOST: postgres
      DB_PORT: 5432
    volumes:
      - ./:/app
    command:
      - -f=/app
      - --local
      - --batch-size=50

This example sets the batch size to 50.

Why change the batch size?

Using a smaller batch size can reduce memory usage and not leave users hanging for large queries. In otherwords, your application can be more responsive.