Troubleshooting

When working with Prisma Accelerate, you may encounter errors often highlighted by specific error codes during development and operations. It is important to understand the meaning of these errors, why they occur, and how to resolve them in order to ensure the smooth operation of your applications. This guide aims to provide insights and steps to troubleshoot specific error codes encountered with Prisma Accelerate.

P6009 (ResponseSizeLimitExceeded)

This error is triggered when the response size from a database query exceeds the configured query response size limit. We've implemented this restriction to safeguard your application performance, as retrieving data over 5MB can significantly slow down your application due to multiple network layers. Typically, transmitting more than 5MB of data is common when conducting ETL (Extract, Transform, Load) operations. However, for other scenarios such as transactional queries, real-time data fetching for user interfaces, bulk data updates, or aggregating large datasets for analytics outside of ETL contexts, it should generally be avoided. These use cases, while essential, can often be optimized to work within the configured query response size limit, ensuring smoother performance and a better user experience.

Possible causes for P6009

Transmitting images/files in response

This error may arise if images or files stored within your table are being fetched, resulting in a large response size. Storing assets directly in the database is generally discouraged because it significantly impacts database performance and scalability. In addition to performance, it makes database backups slow and significantly increases the cost of storing routine backups.

Suggested solution: Configure the query response size limit to be larger. If the limit is still exceeded, consider storing the image or file in a BLOB store like Cloudflare R2, AWS S3, or Cloudinary. These services allow you to store assets optimally and return a URL for access. Instead of storing the asset directly in the database, store the URL, which will substantially reduce the response size.

Over-fetching of data

In certain cases, a large number of records or fields are unintentionally fetched, which results in exceeding the configured query response size limit. This could happen when the where clause in the query is incorrect or entirely missing.

Suggested solution: Configure the query response size limit to be larger. If the limit is still exceeded, double-check that the where clause is filtering data as expected. To prevent fetching too many records, consider using pagination. Additionally, use the select clause to return only the necessary fields, reducing the response size.

Fetching a large volume of data

In many data processing workflows, especially those involving ETL (Extract-Transform-Load) processes or scheduled CRON jobs, there's a need to extract large amounts of data from data sources (like databases, APIs, or file systems) for analysis, reporting, or further processing. If you are running an ETL/CRON workload that fetches a huge chunk of data for analytical processing then you might run into this limit.

Suggested solution: Configure the query response size limit to be larger. If the limit is exceeded, consider splitting your query into batches. This approach ensures that each batch fetches only a portion of the data, preventing you from exceeding the size limit for a single operation.

P6004 (QueryTimeout)

This error occurs when a database query fails to return a response within the configured query timeout limit. The query timeout limit includes the duration of waiting for a connection from the pool, network latency to the database, and the execution time of the query itself. We enforce this limit to prevent unintentional long-running queries that can overload system resources.

The time for Accelerate's cross-region networking is excluded from the configured query timeout limit limit.

Possible causes for P6004

This error could be caused by numerous reasons. Some of the prominent ones are:

High traffic and insufficient connections

If the application is receiving very high traffic and there are not a sufficient number of connections available to the database, then the queries would need to wait for a connection to become available. This situation can lead to queries waiting longer than the configured query timeout limit for a connection, ultimately triggering a timeout error if they do not get serviced within this duration.

Suggested solution: Review and possibly increase the connection_limit specified in the connection string parameter when setting up Accelerate in a platform environment (reference). This limit should align with your database's maximum number of connections.

By default, the connection limit is set to 10 unless a different connection_limit is specified in your database connection string.

Long-running queries

Queries may be slow to respond, hitting the configured query timeout limit even when connections are available. This could happen if a very large amount of data is being fetched in a single query or if appropriate indexes are missing from the table.

Suggested solution: Configure the query timeout limit to be larger. If the limit is exceeded, identify the slow-running queries and fetch only the necessary data. Use the select clause to retrieve specific fields and avoid fetching unnecessary data. Additionally, consider adding appropriate indexes to improve query efficiency. You might also isolate long-running queries into separate environments to prevent them from affecting transactional queries.

Database resource contention

A common yet challenging issue is when other services operating on the same database perform heavy analytics or data processing tasks, significantly consuming database resources. These operations can monopolize database connections and processing power, leading to a scenario where even simple queries cannot be executed in a timely manner. This "busy" or "noisy" database environment can cause queries that are typically fast to run slowly or even timeout, particularly during periods of high activity from other services.

Users often rely on CPU and memory usage metrics to gauge database load, which can be misleading. While these are important indicators, they might not fully represent the database's operational state. Direct metrics like the number of reads, writes, and wait times offer a clearer view of the database's performance and should be monitored closely. A noticeable degradation in these metrics, especially in the absence of changes to the queries or data model, suggests that external pressures are affecting database performance.

Suggested solution: If normally quick queries are intermittently slow or timing out without any modifications to them, it's probable that competing queries are exerting pressure on the same database tables. To diagnose this, adopt monitoring tools or leverage your database's inherent capabilities to observe reads, writes, and wait times. Such monitoring will unveil activity patterns or spikes that align with the observed performance dips.

Moreover, it's crucial to periodically scrutinize and refine essential queries and verify that tables are properly indexed. This proactive approach minimizes the vulnerability of these queries to slowdowns caused by competing workloads.

Considerations for P6009 and P6004 errors

For runtimes that support Prisma ORM natively, you could consider creating two PrismaClient Instances. One with the Accelerate connection string (prefixed with prisma://) and the other one with the direct database connection string (prefixed with postgres://, mysql:// etc). The main idea behind this approach is to bypass Accelerate for certain specific queries.

However, please note that the available connections would be split between both of your PrismaClient Instances. It's crucial to understand the implications of managing multiple instances, particularly in regards to direct database connections. Utilizing a PrismaClient instance with a direct database connection string means that this connection will interact directly with your database.

This approach requires careful consideration because the direct connections and those managed by Accelerate share the same underlying database connection pool. This can lead to competition for resources, potentially affecting the performance and availability of your database services.

Additionally, direct connections could have a significant impact on your database's performance and availability. Operations that consume a considerable amount of resources could potentially degrade the service for other users or processes that rely on the same database.

If your application's runtime environment supports Prisma ORM natively and you're considering this strategy to circumvent P6009 and P6004 errors, you might create two PrismaClient instances:

1. An instance using the Accelerate connection string (prefixed with prisma://) for general operations.
2. Another instance with the direct database connection string (e.g., prefixed with postgres://, mysql://, etc.) for specific operations anticipated to exceed the configured query limit timeout or to result in responses larger than the configured query response size limit.

export const prisma = new PrismaClient({
  datasourceUrl: process.env.DIRECT_DB_CONNECTION,
})

export const prismaAccelerate = new PrismaClient({
  datasourceUrl: process.env.ACCELERATE_CONNECTION,
}).$extends(withAccelerate())

This setup allows you to strategically direct certain operations through the direct connection, mitigating the risk of encountering the aforementioned errors. However, this decision should be made with a comprehensive understanding of the potential consequences and an assessment of whether your database infrastructure can support this additional load without compromising overall performance and availability.

Also see why doesn’t Accelerate fall back to the direct connection string during a service disruption?

P6008 (ConnectionError|EngineStartError)

This error indicates that Prisma Accelerate cannot establish a connection to your database, potentially due to several reasons.

Possible causes for P6008

Database Not Publicly accessible

If your database is within a VPC or access is limited to specific IP addresses, you might encounter this error if static IP is not enabled for Accelerate or if the static IPs are not permitted in your database firewall.

Suggested solution: Enable static IP for Accelerate and configure your database firewall to allow access from the provided static IP addresses.

Unreachable Database Host/Port

If the database’s server address (hostname) and port are incorrect or unreachable then you may encounter this error.

Suggested solution: Verify the hostname/port of the database connection string that was provided while creating the Prisma Accelerate project. Additionally, attempt to connect to the database using a Database GUI tool (e.g., Prisma Studio, TablePlus, or DataGrip) for further investigation.

Incorrect username/password/database name

This error can happen when the wrong credentials are provided to Prisma Accelerate, preventing it from establishing a connection to your database.

Suggested solution: Verify the correctness of your database's username, password, and name in the connection string provided to Prisma Accelerate. Ensure that these credentials match those required by your database. Testing the connection using a direct database GUI tool can also help in confirming if the provided credentials are correct.