Joe Wilson <[EMAIL PROTECTED]> wrote: > --- Tom Briggs <[EMAIL PROTECTED]> wrote: > > For clarity, my definition of small is about 200GB, so I'm not > > selling SQLite short here... > > Are you able to get decent performance out of sqlite3 for a 200GB database? > > How much RAM do you have on such a machine? >
Whenever you start a new transaction, SQLite has to allocate and clear a bitmap used to record which pages have changes in the database file. The size of this bitmap is proportional to the size of the database file. The size of the bitmap is 256 bytes per megabyte of database file assuming a 1KiB page size. That translates into about 52MB for a 200GiB database. This is doable, but probably not optimal. Methods for reducing the memory requirements of this bitmap (so that it is proportional to the size of the change rather than the size of the database) have been proposed, but we have not taken any steps toward implementing them since the current approach works well enough. But as people start to push SQLite into the 100GiB size and beyond, we will likely revisit that decision. -- D. Richard Hipp <[EMAIL PROTECTED]> ----------------------------------------------------------------------------- To unsubscribe, send email to [EMAIL PROTECTED] -----------------------------------------------------------------------------