-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 Hi,
the FAQ of qemu describes Sqlite to be threadsafe [1]. The "threadsafeness" can e.g. be chosen at compiletime [2]. If several Sqlite instances try to access the same database file on a system, the database file gets locked via simple file locks [3]. Those files can also be located on network filesystem like NFS or CIFS. [4] describes, that there might be some broken NFS implementations, which have apparently issues with file locking.... I'm working on a project where it is necessary that the Sqlite database is stored on a networking filesystem and several other clients have access to that file. I first use sshfs-fuse when i realized, that sshfs-fuse is not able to forward file locks. So I got (of course) malformed databases. Now my Question: According to [4], it seems that NFS also has problems with sharing locks. So why does Sqlite make use of file locks instead of writing those locks (including a timestamp for expiration) inside the database file or by touching dotfiles for locking? [1] : http://www.sqlite.org/faq.html#q6 [2] : http://www.sqlite.org/compile.html#threadsafe [3] : http://www.sqlite.org/howtocorrupt.html Chapter 2.1 [4] : http://www.sqlite.org/faq.html#q5 Regards, - -- Ralf Ramsauer PGP: 0x8F10049B -----BEGIN PGP SIGNATURE----- Version: GnuPG v2.0.20 (GNU/Linux) Comment: Using GnuPG with Thunderbird - http://www.enigmail.net/ iQIcBAEBAgAGBQJSClJeAAoJEPovtFKPEASbWbMQAJPhmoCxoWWbDDFxAtNVSVAo Jd9HmuUsPxGtKUVW+5yUvyHbtUcKaL9dRLq5uzswN3PiWfa0ro0h6FcWXGpwZYwG +wVopcPHbCNxnbLwCQ05xdgtrJ7eLgvD5zj6/Y4ud+9OTHwLm27hjXorZX9Lt9qG aq6sEMynuVGv136xWuJTDxPjJdgCtsQSaT2VMeArIA+Mn92CkqhK5YHYZ37RVMRh l6wmX7U30d6cr7WqkV/wfVR7xjvQruum+4kMCAovpnNQJOTMa7m4Ky6SiclVN4bu 6AxEjhX7vk565PpWLm4UoMUma7TXHvd7FFCCKdagEe28ZF8Q+Bl2I1Lyn0+AD715 THCVgbpXms6IYptBHRQxuCC4/saGOMICdyn2ZBHDj6XmTYhR2d+3Reu5Men42QWI QHY2AEcmQANN+dRWvUtwfKW738nGGqgDsB97cz8iUI3eWfY/VlKe5ZbPPB2RM/mc w+yb1YxKFpAWXyVBPUC8HrT+AB2fWzqG+fijsaAeWfNxGt8cQivnBThmyf+JrJOC A+lQAwHiADY7lyTG3q8VgwmznRCPGLUd2M246h2hvSBfyG+/OLd+iH6Kk5E9Grnl jK6gRotY7A7T6of+sOwwcFbAtAZ0r8DGflGw0BoIglJjecstp3XdkBgxByXPABQs ohEq/wiS/PDKaMp2rP95 =MNHI -----END PGP SIGNATURE----- _______________________________________________ sqlite-users mailing list sqlite-users@sqlite.org http://sqlite.org:8080/cgi-bin/mailman/listinfo/sqlite-users
