could not open temporary statistics file "pg_stat_tmp/global.tmp": No space left on device

The "No space left on device" error you're encountering while importing nested projects is typically caused by one of several issues related to disk space, even when it appears you have sufficient storage available.

Here are some potential causes and solutions:

1. Check actual disk usage: Run df -h to verify which partitions are full. This will show you the usage across all filesystems and help identify where the space constraint is occurring.

2. Check inode usage: Sometimes the issue isn't about storage space but about running out of inodes (file index nodes). Run df -i to check if your inodes are exhausted. This is a common cause of "No space left" errors even when disk space appears available.

3. Clean up unnecessary files: Remove large, unnecessary files, old Docker images/containers, or temporary files that might be consuming space.

4. Temporary directory issues: The PostgreSQL error specifically mentions a temporary statistics file, which suggests the temporary directory might be full. Check the space in the directory where PostgreSQL stores temporary files.

5. Docker cleanup: If you're using Docker, run docker system prune or docker system prune -a --volumes for a more thorough cleanup to free up space.

6. Resize partitions: You might need to resize partitions to allocate more space to the filesystem where PostgreSQL is trying to write temporary files.

7. Adjust PostgreSQL configuration: Consider modifying PostgreSQL's configuration to use a different directory for temporary files if the current location has space constraints.

If you've recently increased your storage volume but are still experiencing this error, remember that you may need to extend the corresponding filesystem to make the additional space available to your system.

Sources
Cloud 9 - git and no space left on device | AWS re:Post
AWS CodeBuild Failed with Error: no space left on device | AWS re:Post
Error to update runtime python 3.11 | AWS re:Post
Backup interrupt for no space | AWS re:Post