Understanding of checkpoint not completed, checkpoint

Understanding of checkpoint not completed, checkpoint

Assume that the database has two log groups: log1 and log2. First, --> log1 --> log2 --> log1. At this time (log2 switches to log1), the checkpoint will be flush dirty block to datafile, this triggers DBWn to write dirty buffer. log1 can be used only after all dirty blocks covered by log1 are written to datafile. If DBWn writing is too slow, LGWR must wait for DBWn to complete, then "checkpoint not completed!"

The answer from others is:

Log1-> log2, trigger checkpoint 1
After log2 is full,
Log2-> log1, trigger checkpoint 2
But if checkpoint 1 is still not finished, then LGWR must wait. This is "logfile switch (checkpoint incompleted)" event.

In my understanding

1. the checkpoint can be successfully switched.

2. checkpoint1 blocks log2-> log1 switching.

3. If no redo logs are available, the data will be blocked and the database will be temporarily hang. (The reason is as follows)

I don't know, right? please correct me ~

Before a change is done in the buffer cache a change vector (file, block, row, value) about this change is written to the redo buffer. first the change of the undo block to be made soon is tracked (L ). then the change is done in the buffer cache (M ). then the change of the table block to be made soon is tracked (N ). then the insert to the table block is done in the buffer cache (O ). all actions up to now where done by the server process (P ). finally it returns the control to the client process (Q ).

The redo cannot be tried, and the transaction cannot proceed normally.

What does setup was not completed successfully on the computer mean?

The program is not successfully installed.
The installation file may be corrupted. There may be other reasons. Depending on your specific installer name

When my PS is liquefied with a filter, what is The operation cocould not be compLeted?

I have never met anyone. Maybe it's a conflict with any software or filter!