(ITS#8418) mdb_load performance

Full_Name: Andrew Schorr Version: lmdb 0.9.18 OS: Linux URL: ftp://ftp.openldap.org/incoming/ Submission from: (NULL) (38.76.0.51)

I patched mdb_load to add an option to set the mapsize with -T, as per open issue #8417. I then used it to load a 7 GB text file, and I found that the calls to mdb_txn_commit after every 100 mdb_cursor_put calls really slows down performance. If one comments out the batching, it goes much faster. And even faster is to avoid the cursor and just call mdb_put in a loop. Is there a reason mdb_load commits after every 100 puts?