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Stuck with the ‘Amazon EC2 instance slow and unresponsive’ issue? We can help you with this!
Here, at Bobcares, we often receive similar AWS queries from our customers as a part of our AWS Support Services.
Today, let’s see the steps followed by our Support Engineers to resolve the EC2 instance’s slow and unresponsive issue.
EC2 instance slow and unresponsive
EC2 server becomes unresponsive or slow due to several reasons. It includes issues with the external service that the instance depends on, network connectivity issues, or disk thrashing.
Now we are going to see one of the common causes for the slowness or unresponsiveness and it is depleted I/O burst credits on the gp2 root volume where gp2 is the default storage drive for the root volume.
How to check I/O burst credit balance
- Log in to the AWS Management Console and open the Amazon EC2 console.
2. Select instances and then select the instance.
3. Select the Volume ID of the root device from the Storage tab.
4. Then select the Monitoring tab for the EBS volume, and from there we can find the Burst Balance metric.
If the burst balance is 0%, it means that all the credits are used. Also, the volume cannot burst above its baseline performance level. Therefore, we need to perform any of the following methods to resolve this issue with burst balance.
Evaluate the IOPS requirements and alter the volume
- At first, open Amazon CloudWatch and we have to find the root EBS volume’s VolumeReadOps and VolumeWriteOps metrics.
2. Then find the peak levels of VolumeReadOps and VolumeWriteOps by using the CloudWatch Sum statistic.
3. Then add the two values.
For Example: VolumeReadOps = 865,000 and VolumeWriteOps = 186,000
Total sum = VolumeReadOps+VolumeWriteOps = 1051000
4. Then divide the total sum by the no. of seconds in the measurement interval to estimate how many IOPS are needed.
If the Measurement interval is 10 minutes, that is 600sec, then IOPS = 1051000 / 600 = 1752
The baseline performance for gp2 volumes scales at 3 IOPS per GB of volume size. Therefore a volume with 1752 IOPS must be scaled up to 584 GB(1752 / 3=584)to enhance the performance.
Modify the distribution of workload
If we have multiple applications in our Amazon EC2 instance, then it will compete for the root EBS volume’s IOPS. The IOPS demand will increase as the workload increases. For enhancing the performance of instances, we need to consider using additional non-root EBS volumes and root volume for your applications and for the operating system respectively.
[Need help with more AWS queries? We’d be happy to assist]
Conclusion
To conclude, today we discussed the steps followed by our Support Engineers to help our customers to resolve the ‘Amazon EC2 instance slow and unresponsive’ issue.
