Graph hangs and is unkillable
A graph can sometimes hang and be unkillable if some network connection in it hangs.
Set a shorter
tcp-keepalive so that the connection times out earlier.
The default value on Linux is 2 hours (7,200 seconds). You can set it to 10 minutes (600 seconds).
The file descriptor can be closed manually using
See How to close file descriptor via Linux shell command.
Graph run in Worker is Slow
It may be caused by slow data storage.
vmstat 1 30.
If you see high values under
bo columns, it might be that case.
Another tool to confirm or disconfirm slow data storage as possible cause is