Error
Error Code:
225
MongoDB Error 225: Transaction Expired or Aged Out
Description
Error 225, 'Transaction Too Old', indicates that a multi-document transaction has exceeded its configured lifetime limit or has been implicitly aborted by MongoDB. This typically happens when a transaction remains open for too long, preventing it from being committed successfully.
Error Message
Transaction Too Old
Known Causes
3 known causesTransaction Lifetime Limit
The transaction remained open for longer than the `transactionLifetimeLimitSeconds` configured on the MongoDB replica set.
Slow Application Logic
The application client held the transaction open while performing extensive, time-consuming operations before attempting to commit or abort.
Network Issues
Significant network delays or temporary disconnections prevented the transaction's commit or abort command from reaching the MongoDB server in time.
Solutions
3 solutions available1. Increase Transaction Lifetime easy
Adjust the maximum time a transaction can remain open.
1
Identify the `transactionLifetimeLimitSeconds` parameter in your MongoDB configuration. This parameter defines the maximum time in seconds a transaction can remain open before it is automatically aborted.
Refer to your `mongod.conf` file or the command-line options used to start your mongod instances.2
Increase the value of `transactionLifetimeLimitSeconds`. The default is 120 seconds. Consider increasing it to a value that accommodates your longest-running transactions.
Example: To set the limit to 5 minutes (300 seconds):
In `mongod.conf` (YAML):
yaml
setParameter:
transactionLifetimeLimitSeconds: 300
Or via command line:
bash
--setParameter transactionLifetimeLimitSeconds=300
3
Restart your `mongod` instances for the changes to take effect.
Use your system's service manager (e.g., `sudo systemctl restart mongod`) or the command used to start your MongoDB processes.2. Optimize Transaction Logic medium
Reduce the duration of your transactions.
1
Analyze your application code that initiates and manages MongoDB transactions. Identify operations within the transaction that might be taking excessively long.
This involves reviewing your application's database interaction logic, potentially using profiling tools or logging to pinpoint slow operations.2
Break down large or complex transactions into smaller, more manageable units. If possible, perform independent operations outside of the transaction.
Example: Instead of a single transaction that reads, modifies, and then writes multiple documents, consider performing read operations, processing data in your application, and then committing a transaction with only the write operations.3
Ensure that any external API calls or complex computations within a transaction are efficient and have reasonable timeouts.
If your transaction relies on external services, ensure those services are responsive and that your application handles potential delays gracefully.4
Consider implementing retry logic for parts of the transaction that are prone to intermittent delays, rather than holding the entire transaction open for an extended period.
This might involve application-level retries for specific operations that can be idempotent.3. Monitor Transaction Activity medium
Gain visibility into ongoing transactions to identify problematic ones.
1
Use the `db.transactions.find()` command in the `mongo` shell to view active transactions. This command shows details about ongoing transactions, including their start time and duration.
javascript
db.transactions.find()
2
Filter transactions by duration or start time to identify those that are approaching or exceeding the `transactionLifetimeLimitSeconds`. You can use aggregation pipelines for more sophisticated filtering.
Example: Find transactions older than 60 seconds:
javascript
db.transactions.aggregate([
{
$match: {
"lastActive": { $lt: new Date(Date.now() - 60000) }
}
}
])
3
Integrate MongoDB's server status and diagnostic data into your monitoring system (e.g., Prometheus, Datadog). Look for metrics related to transaction counts and durations.
Consult the MongoDB documentation for available metrics and how to export them.4
Set up alerts based on transaction duration or count to proactively notify administrators when transactions are becoming excessively long.
Configure your monitoring system to trigger alerts based on the metrics gathered in the previous steps.