database/sql: close connection if db.numOpen > db.maxOpen
Bug Description:
When reduce db.maxOpen via db.SetMaxOpenConns, the unnecssary
connections won't been released until all other connections are free.
Fixes #9453
Change-Id: I9afb2e4b184139b31029ae53d7f5fd1fdb8d8d7e
Reviewed-on: https://go-review.googlesource.com/2200
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
diff --git a/src/database/sql/sql.go b/src/database/sql/sql.go
index b0e8894..0a84163 100644
--- a/src/database/sql/sql.go
+++ b/src/database/sql/sql.go
@@ -782,6 +782,9 @@
// If a connRequest was fulfilled or the *driverConn was placed in the
// freeConn list, then true is returned, otherwise false is returned.
func (db *DB) putConnDBLocked(dc *driverConn, err error) bool {
+ if db.maxOpen > 0 && db.numOpen > db.maxOpen {
+ return false
+ }
if c := len(db.connRequests); c > 0 {
req := db.connRequests[0]
// This copy is O(n) but in practice faster than a linked list.
