Kim Gräsman wrote: > I would expect SQLite to allocate a page cache per session.
There is typically one page cache instance per connection. (A connection is what you get from sqlite3_open*(); a session would be what you get from sqlite3session_create().) > So if we want to use SQLITE_CONFIG_PAGECACHE to provide a > preallocated buffer for the page cache, it looks like we have to > provide it for the worst case, i.e. max(page size) * sum(cache > requirements for all sessions). Is that the case? Yes; the SQLITE_CONFIG_PAGECACHE memory is used by all cache instances. > is SQLITE_CONFIG_PAGECACHE used to specify an arena for page caches, > or a buffer for pages between all sessions? A page cache instance is a list of pages; memory for each page is allocated individually. > Since we have different page sizes (512 bytes and 4K respectively) I'm > worried we'll have lots of dead space if SQLITE_CONFIG_PAGECACHE is > set up for 4K pages and requests for 512-byte pages are served from > there directly. If your use case is more complex than the simple mechanism offered by SQLITE_CONFIG_PAGECACHE, consider using SQLITE_CONFIG_PCACHE2 (or SQLITE_CONFIG_MALLOC). Regards, Clemens _______________________________________________ sqlite-users mailing list sqlite-users@mailinglists.sqlite.org http://mailinglists.sqlite.org/cgi-bin/mailman/listinfo/sqlite-users
