-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 Michael Han wrote: > My question is can I safely turn off this flag if the underlying file > system supports journaling?
By default journaling file systems only use their journal for meta-data (eg directory entries and allocation information). They do not guarantee that the contents of files are consistent. Some do let you journal file contents too, but that then means file contents changes are written to the journal and the file (ie double the amount of data is written to disk). There is no way around the slowness you get when ensuring data is physically flushed to the disk (laws of physics!). The most effective way to mitigate the effect is by grouping as many changes as possible into single transactions. You can also get hard disks that spin faster (also louder, use more energy and more expensive), use ones that don't spin at all although SSD writing speeds are variable or use a controller and drive that are battery backed so they can lie about data actually being on the platters. Roger -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.9 (GNU/Linux) Comment: Using GnuPG with Mozilla - http://enigmail.mozdev.org iEYEARECAAYFAkqFil8ACgkQmOOfHg372QSiSACg0/GZptBC5aNN1F2kjxtB3Gg9 lB4AmweoQ8+/6YrmLF1QlCA9wkLOFuTI =gMT6 -----END PGP SIGNATURE----- _______________________________________________ sqlite-users mailing list sqlite-users@sqlite.org http://sqlite.org:8080/cgi-bin/mailman/listinfo/sqlite-users
