steveloughran commented on pull request #2584: URL: https://github.com/apache/hadoop/pull/2584#issuecomment-764587055
Thomas, to clarify a bit more yes, an FS can choose to ignore an option, -but it must recognise the option and so make a conscious decision "this doesn't matter" * so with the standard length/read policy options, an FS can concude "I see that and don't support it", and just ignore it -a decision made on an option-by-option basis. * if something unrecognised comes in as .must() the FS must raise an exception "I don't recognise that". * if something it does recognise as a .must() which it knows it doesn't support and which it MUST be able to, then it MUST raise an exception. Example: vectored IO will only work if the FS supports seek, which ftp doesn't. Assuming we add an option to say "I Want vectored IO" then all filesystems will get this out the box as a well known-and-supported feature, but ftp will need some explicit code to say "fail if vectored IO is requested" ---------------------------------------------------------------- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. For queries about this service, please contact Infrastructure at: [email protected] --------------------------------------------------------------------- To unsubscribe, e-mail: [email protected] For additional commands, e-mail: [email protected]
