On May 31 14:19, Warren Young wrote: > On 5/31/2013 13:58, Warren Young wrote: > > > >The SQLite code prefers POSIX advisory locks, but it can fall back to > >BSD locks if it has to. > > Just to clarify, when I say "POSIX locks" I always mean new style > fcntl() locks. There are no calls to lockf() in sqlite3.c. > > >I'm not sure why it doesn't just > >blindly try the lock. > > On reflection, I'm sure it has something to do with maintaining high > concurrency. If it knows its near-future DB file write is going to > get blocked, it can choose to do something else while the existing > DB lock holders finish. > > By contrast, SQLite's flock() based locking is documented as being > much more brute-force, resulting in much lower concurrency.
Makes sense, given that flock is not record but file locking. Corinna -- Corinna Vinschen Please, send mails regarding Cygwin to Cygwin Maintainer cygwin AT cygwin DOT com Red Hat -- Problem reports: http://cygwin.com/problems.html FAQ: http://cygwin.com/faq/ Documentation: http://cygwin.com/docs.html Unsubscribe info: http://cygwin.com/ml/#unsubscribe-simple
