jitendra-nalwaya
commented
1 year ago Hi @jhouserizer,
Used two sentinel files to identify last shutdown status in below scenarios -
1) When customer upgrade their environment with this enhancement. 2) Remove directory structure explicitly by customer. 3) Remove directory structure using destroy/destroyall methods.
On startup,
- If both files do not exist then we can't identify last shutdown state, therefore we will create 'unCleanShutdown' file.
- If 'unCleanShutdown' file exist then we will remove directory structure and on shutdown we will delete 'unCleanShutdown' file and create 'cleanShutdown' file.
- If 'cleanShutdown' file exist then we will delete 'cleanShutdown' file and create 'unCleanShutdown' file.
We can use single sentinel file as well if we write some content in it to identify the last shutdown state.
Could you please elaborate below statement - Managing two files is non-atomic, and therefore more prone to leaving one behind when it need not be, or etc.?
Hi @jitendra-nalwaya ,
Could you please explain the purpose of using two sentinel files ("cleanShutdown" and "unCleanShutdown")?
What does using two files rather than one provide? why can't the presence of "unCleanShutdown" indicate non-clean, and the absence of it represent clean? or why can't the presence of "cleanShutdown" represent clean, and the absence represent non-clean?
Managing two files is non-atomic, and therefore more prone to leaving one behind when it need not be, or etc.?
There may be an advantage to using two files, and if so, can you please explain?