Innodb optimistic insertion fails due to insufficient space and enters the pessimistic insertion stage. The size of this space is limited in innodb stage.

Innodb optimistic insertion fails due to insufficient space and enters the pessimistic insertion stage. The size of this space is limited in innodb stage.

Btr_cur_optimistic_insert {

...

/* Check whether there is sufficient space for future record update during split page */

If (leaf &&! Zip_size & dict_index_is_clust (index)

& Page_get_n_recs (page)> = 2

& Dict_index_get_space_reserve () + rec_size> max_size

& (Btr_page_get_split_rec_to_right (cursor, & dummy)

| Btr_page_get_split_rec_to_left (cursor, & dummy ))){

Gotofail;

}

...

}

Dict_index_get_space_reserve () + rec_size> max_size

Dict_index_get_space_reserve () = 1024, that is, when the rec_size of the 1024 + record is greater than the max_size of the current page's free space, optimistic insertion fails, enters the pessimistic insertion stage, and B + split occurs.

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