mdbx: extra backlog's page for MDB_LIFORECLAIM.

Change-Id: I24d656de96a4bc3a3d4f6409db75868b818a4233
This commit is contained in:
Leo Yuriev 2016-04-26 22:48:08 +03:00
parent 7ae6c0f768
commit 745bdd346a

17
mdb.c
View File

@ -3279,7 +3279,7 @@ static MDB_INLINE int
mdb_backlog_size(MDB_txn *txn)
{
int reclaimed = txn->mt_env->me_pghead ? txn->mt_env->me_pghead[0] : 0;
return reclaimed += txn->mt_loose_count;
return reclaimed + txn->mt_loose_count;
}
/* LY: Prepare a backlog of pages to modify FreeDB itself,
@ -3288,16 +3288,21 @@ mdb_backlog_size(MDB_txn *txn)
static int
mdb_prep_backlog(MDB_txn *txn, MDB_cursor *mc)
{
if (mdb_backlog_size(txn) <= mc->mc_db->md_depth) {
/* LY: extra page(s) for b-tree rebalancing */
const int extra = (txn->mt_env->me_flags & MDB_LIFORECLAIM) ? 2 : 1;
if (mdb_backlog_size(txn) < mc->mc_db->md_depth + extra) {
int rc = mdb_cursor_touch(mc);
if (unlikely(rc))
return rc;
/* LY: one more page is required if a b-tree needs rebalancing */
if (unlikely(mdb_backlog_size(txn) < 1)) {
while (unlikely(mdb_backlog_size(txn) < extra)) {
rc = mdb_page_alloc(mc, 1, NULL, MDB_ALLOC_GC);
if (unlikely(rc && rc != MDB_NOTFOUND))
return rc;
if (unlikely(rc)) {
if (unlikely(rc != MDB_NOTFOUND))
return rc;
break;
}
}
}