Investigate why image creating take so long

added Backlog label

added Debugging label

Gemini's summary of the possible issues is helpful. It seems like a reasonably comprehensive list of areas to investigate:

https://www.google.com/search?q=qcow2+glance+slow+upload

Looks like you can now export the text from Gemini answers, but I can't seem to paste it. :)

A slow upload of a qcow2 image to Glance in OpenStack can occur due to several reasons, including: network bandwidth limitations, inefficient qcow2 image format (especially with high fragmentation), insufficient disk space on the Glance server, incorrect Glance configuration, or issues with the underlying storage backend; it's important to investigate the specific environment to identify the bottleneck and optimize accordingly. 
Potential causes and solutions:

    Network Bandwidth:
        Check network connectivity: Verify that the network between the source of the qcow2 image and the Glance server has adequate bandwidth to handle large image uploads.
        Optimize network settings: Consider adjusting MTU or network settings to improve transfer efficiency. 
    qcow2 Image Issues:
        Image Fragmentation: If the qcow2 image is highly fragmented due to multiple snapshots, consider converting it to a less fragmented format like raw before uploading to Glance.
        Large Image Size: Break down very large qcow2 images into smaller chunks for upload to minimize the impact on network bandwidth. 
    Glance Server Configuration:
        Storage Backend: Check if the configured Glance storage backend is optimized for large image uploads and consider switching if necessary.
        Cache settings: Review the Glance cache configuration to ensure it is not causing bottlenecks during upload.
        Glance API settings: Verify that the Glance API settings are not limiting upload speeds (e.g., chunk size). 
    Disk Space on Glance Server:
        Available Disk Space: Ensure sufficient disk space is available on the Glance server to store the uploaded image. 

Troubleshooting Steps:

    Monitor Upload Progress:
    Use tools to monitor the upload speed and identify any sudden slowdowns or pauses. 

Check Glance Logs:
Review the Glance logs for any errors or warnings related to the upload process. 
Analyze qcow2 Image:
Use tools to assess the fragmentation level of the qcow2 image. 
Optimize qcow2 Image:
Consider converting the qcow2 image to a different format if fragmentation is high.