High availability and short response times are necessary, making background jobs an indispensable tool regardless of the application’s scale.
Overview
The article discusses the importance of high availability in applications, particularly during peak traffic periods, and how offloading work into background jobs can enhance performance and user experience. It outlines the benefits of background jobs, including improved response times, handling traffic spikes, and managing error-prone tasks efficiently.
What You'll Learn
1
How to offload time-consuming tasks to background jobs
2
Why background jobs improve application availability during traffic spikes
3
When to implement retries and redundancy in background job processing
Key Questions Answered
What is high availability in the context of web applications?
High availability refers to the ability of an application to remain accessible and functional for users, allowing meaningful interactions without delays. It goes beyond server uptime, ensuring that users can perform actions like making purchases without encountering errors or downtime.
How do background jobs enhance response times?
Background jobs decouple time-consuming tasks from the main request-response cycle, allowing the application server to respond quickly to user requests. This leads to improved overall system availability and user experience, especially during high traffic periods.
What are common tasks suitable for offloading to background jobs?
Common tasks that can be offloaded include sending emails, processing images and videos, firing webhooks, rebuilding search indexes, importing large datasets, and cleaning up stale data. Offloading these tasks helps maintain application responsiveness.
What challenges are associated with background job processing?
Challenges include breaking changes to job parameters, the lack of exactly-once delivery, non-transactional queuing, local transaction issues, out of order delivery, and managing long-running jobs. These challenges require careful handling to maintain system integrity.
Key Statistics & Figures
Peak sales during BFCM 2020
100 Million USD per hour
This peak sales figure highlights the need for high availability in applications during significant traffic events.
Requests handled by Shopify
170k requests per second
This statistic underscores the importance of background jobs in maintaining application performance under heavy load.
Key Actionable Insights
1Implement background jobs to handle non-essential tasks asynchronously.By offloading tasks like email sending or image processing, your application can respond to user requests more quickly, enhancing user satisfaction and maintaining high availability.
2Utilize message queues to manage communication between application servers and workers.Message queues allow for asynchronous processing, enabling your application to handle spikes in traffic without degrading performance, as tasks can be queued and processed independently.
3Consider implementing retries and redundancy for error-prone tasks.This ensures that if a job fails, it can be retried without affecting the user experience, which is particularly important for tasks involving unreliable third-party services.
Common Pitfalls
1
Failing to manage breaking changes in job parameters can lead to application errors.
When the client and worker run different software versions, it can break the application if job parameters are incompatible. Implementing backward compatibility during deployments can help mitigate this issue.
2
Not addressing the challenge of non-transactional queuing can result in inconsistent application states.
If jobs are queued before the transaction committing operational data is completed, it may lead to jobs failing to find the necessary data, causing inconsistencies. Using the outbox pattern can help ensure jobs are queued only after data is committed.
Related Concepts
Asynchronous Processing
Message Queues
Event-driven Architecture
Microservices