diff options
Diffstat (limited to 'src/include/access/gist_private.h')
| -rw-r--r-- | src/include/access/gist_private.h | 15 |
1 files changed, 15 insertions, 0 deletions
diff --git a/src/include/access/gist_private.h b/src/include/access/gist_private.h index d9b1fa2fec5..53f794f3b9e 100644 --- a/src/include/access/gist_private.h +++ b/src/include/access/gist_private.h @@ -22,6 +22,21 @@ #include "utils/rbtree.h" #include "utils/hsearch.h" +/* + * Maximum number of "halves" a page can be split into in one operation. + * Typically a split produces 2 halves, but can be more if keys have very + * different lengths, or when inserting multiple keys in one operation (as + * when inserting downlinks to an internal node). There is no theoretical + * limit on this, but in practice if you get more than a handful page halves + * in one split, there's something wrong with the opclass implementation. + * GIST_MAX_SPLIT_PAGES is an arbitrary limit on that, used to size some + * local arrays used during split. Note that there is also a limit on the + * number of buffers that can be held locked at a time, MAX_SIMUL_LWLOCKS, + * so if you raise this higher than that limit, you'll just get a different + * error. + */ +#define GIST_MAX_SPLIT_PAGES 75 + /* Buffer lock modes */ #define GIST_SHARE BUFFER_LOCK_SHARE #define GIST_EXCLUSIVE BUFFER_LOCK_EXCLUSIVE |