Re: [sqlite] Network share & disk I/O error
On 12 Jul 2018, at 19:11, Richard Hipp wrote: > When network filesystems do not follow the usual semantics of a > filesystem, it can cause problems. > > That said, Firefox and Chrome have for many years stored lots of stuff > in SQLite database files in the users home directory, which is often a > network share, and they have not reported any problems. Hi, ok, that’s good news. So it’s definitely possible to get working. > On the other hand, they (or at least Firefox, I not sure about Chrome) run > with > PRAGMA locking_mode=EXCLUSIVE [1] which tends to bypass most of the > network filesystem bugs, at the expense of restricting database access > to a single process at a time. Ok, we can try that. > Is your system able to live with that restriction and use PRAGMA > locking_mode=EXCLUSIVE? Yes, that shouldn’t be a problem. Thanks. -- Robert M. Münch, CEO M: +41 79 65 11 49 6 Saphirion AG smarter | better | faster http://www.saphirion.com http://www.nlpp.ch signature.asc Description: OpenPGP digital signature ___ sqlite-users mailing list sqlite-users@mailinglists.sqlite.org http://mailinglists.sqlite.org/cgi-bin/mailman/listinfo/sqlite-users
Re: [sqlite] Network share & disk I/O error
With Richards comment, the only additional thing I'd weigh in on is what your remote file server is doing with the physical file. Virus scanners can interfere with the usual operation of your program, and can cause certain things to happen. Because the OS you're running your software on is told that the file is written to successfully, it doesn't necessarily mean that the remote server has actually performed the work. There are a lot of new assumptions that are thrown into the mix when dealing with remote files. Windows machines are notorious for not allowing things to happen to files (IE: Delete/erase/rename/etc) while something external has hold of them, which is a pain when doing file maintenance on larger systems with lots of remote fingers on said file. Linux is more liberal with how it handles file access in that you can do more intentionally damaging things to files (Such as delete/erase/rename/etc) but the problem with that approach is that the client can never be sure its got the most recent data available because the filesystem on the remote end has done something different with the file compared to what your application is expecting, even with single user single connection access. On Thu, Jul 12, 2018 at 12:59 PM, Robert M. Münch < robert.mue...@saphirion.com> wrote: > Hi, > > Context: Users of our app can define a working directory where sqlite > files are stored. This can be a network share. The files are only used by > one user at the time. > > We now saw two crash reports with „Database disk I/O error“ when a > transaction was closed with „END“. Is this a known problem when having > sqlite files on a network share? > > I read about the locking quirks on network share but related this to cases > where a file could be accessed by several users at the same time and an > application trusts the operating system to handle the locking correct. I > don’t understand it that way that using sqlite files from a network share > is per se impossible. > > Any insights on this? > > Viele Grüsse. > > -- > > Robert M. Münch, CEO > M: +41 79 65 11 49 6 > > Saphirion AG > smarter | better | faster > > http://www.saphirion.com > http://www.nlpp.ch > > ___ > 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
Re: [sqlite] Network share & disk I/O error
On 7/12/18, Robert M. Münch wrote: > > We now saw two crash reports with „Database disk I/O error“ when a > transaction was closed with „END“. Is this a known problem when having > sqlite files on a network share? > When network filesystems do not follow the usual semantics of a filesystem, it can cause problems. That said, Firefox and Chrome have for many years stored lots of stuff in SQLite database files in the users home directory, which is often a network share, and they have not reported any problems. On the other hand, they (or at least Firefox, I not sure about Chrome) run with PRAGMA locking_mode=EXCLUSIVE [1] which tends to bypass most of the network filesystem bugs, at the expense of restricting database access to a single process at a time. Is your system able to live with that restriction and use PRAGMA locking_mode=EXCLUSIVE? [1] https://www.sqlite.org/pragma.html#pragma_locking_mode -- D. Richard Hipp d...@sqlite.org ___ sqlite-users mailing list sqlite-users@mailinglists.sqlite.org http://mailinglists.sqlite.org/cgi-bin/mailman/listinfo/sqlite-users
[sqlite] Network share & disk I/O error
Hi, Context: Users of our app can define a working directory where sqlite files are stored. This can be a network share. The files are only used by one user at the time. We now saw two crash reports with „Database disk I/O error“ when a transaction was closed with „END“. Is this a known problem when having sqlite files on a network share? I read about the locking quirks on network share but related this to cases where a file could be accessed by several users at the same time and an application trusts the operating system to handle the locking correct. I don’t understand it that way that using sqlite files from a network share is per se impossible. Any insights on this? Viele Grüsse. -- Robert M. Münch, CEO M: +41 79 65 11 49 6 Saphirion AG smarter | better | faster http://www.saphirion.com http://www.nlpp.ch signature.asc Description: OpenPGP digital signature ___ sqlite-users mailing list sqlite-users@mailinglists.sqlite.org http://mailinglists.sqlite.org/cgi-bin/mailman/listinfo/sqlite-users
