[isabelle-dev] log file where art thou?

[Gerwin Klein]

I noticed recently that log files don't seem to be streamed to disk any more while the session is running, but only appear after "isabelle build" is finished with the session.

Having them on disk directly was very nice for diagnosing non-termination problems in large sessions and left at least some information in the case of bad system crashes (e.g. polyml bugs).

Was this a conscious decision or is it a side effect? I'd be quite keen to get the old behaviour back.

It's possible that java/scala file operations buffer by default and commit to disk only on close or explicit sync. This is usually done for performance, but in case of a log file the standard OS file system caching mechanisms should easily be sufficient (unless we force full sync to disk, which would be slow).

Cheers,
Gerwin

(this is on 3db108d14239)