Database hang in rare cases when process halts out while online freeze is in effect
nars1 opened this issue · comments
Final Release Note
Description
If a database file is frozen online using MUPIP FREEZE -ONLINE -ON -NOAUTORELEASE where autorelease is disabled, it is possible in rare cases for the database to hang if a concurrent process is trying to halt out (and had opened the same database file) at the same time.
Note that GTM-8850 indicates this issue as being fixed in GT.M V6.3-003 (http://tinco.pair.com/bhaskar/gtm/doc/articles/GTM_V6.3-003_Release_Notes.html#GTM-8850) but in our investigation of that code fix, it seems to have only reduced the possibility of the hang, not eliminated it altogether. And we have a test case (under development v63003/gtm8850 subtest in YottaDB/YottaDBtest repo) that demonstrates the issue even with V6.3-003.
Draft Release Note
YottaDB processes detach from database files correctly when a FREEZE -ONLINE is in place. Previously a process could hang waiting on a critical resource while trying to detach, which typically occurs when the process is trying to exit. Note that a similar issue was indicated as fixed in GT.M V6.3-003 (http://tinco.pair.com/bhaskar/gtm/doc/articles/GTM_V6.3-003_Release_Notes.html#GTM-8850) but the fix was incomplete.