Fair comment. We have seen problems: 1. In all versions of Windows based on the 95 kernel, and especially Windows ME (but not the NT kernel since 3.5) 2. At any time if the network infrastructure is unreliable (too many errors or retries) 3. At any time if a client machine misbehaves eg crashes while holding a lock, or attempts its own file accesses etc 4. Recently, apparently related to SMB 3.0+, due to more aggressive performance optimisations.
But if everything is configured right and working right and nothing bad happens then it is highly reliable over very large volumes of transactions. I guess my plea would be to emphasise the need to pay attention to all the details and to warn that there is still a risk of uncontrolled data loss, rather than just branding it as 'broken'. Regards David M Bennett FACS Andl - A New Database Language - andl.org > -----Original Message----- > From: sqlite-users-boun...@mailinglists.sqlite.org [mailto:sqlite-users- > boun...@mailinglists.sqlite.org] On Behalf Of Simon Slavin > Sent: Tuesday, 28 June 2016 7:28 PM > To: SQLite mailing list <sqlite-users@mailinglists.sqlite.org> > Subject: Re: [sqlite] Locking semantics are broken? > > > On 28 Jun 2016, at 9:07am, dandl <da...@andl.org> wrote: > > >> Do not use SQLite for concurrent access over a network connection. > >> Locking semantics are broken for most network filesystems, so you > >> will have corruption issues that are no fault of SQLite. > > > > I have seen this comment made more than once on this list. Is there any > reliable evidence to support this for a Windows-based network? > > Actually, the problem that causes causes people to make that warning occurs > in POSIX. See the beginning of section 6.0 in this page: > > <https://www.sqlite.org/lockingv3.html> > > However, while the above is a definitely known, verifiable problem, with > every implementation of POSIX, we have had occasional reports about locking > problems with Windows as documented in section 9.1 here: > > <https://www.sqlite.org/atomiccommit.html> > > The problem is that with the numerous versions of Windows, File System and > Network system, nobody has come up with a fault which can be reproduced by > the developers. But we do get enough vague reports of problems with Windows > to make us believe that there is something wrong somewhere. > > Simon. > _______________________________________________ > sqlite-users mailing list > sqlite-users@mailinglists.sqlite.org > http://mailinglists.sqlite.org/cgi-bin/mailman/listinfo/sqlite-users _______________________________________________ sqlite-users mailing list sqlite-users@mailinglists.sqlite.org http://mailinglists.sqlite.org/cgi-bin/mailman/listinfo/sqlite-users
