diff options
| -rw-r--r-- | mysql-test/r/sp.result | 19 | ||||
| -rw-r--r-- | mysql-test/t/sp.test | 34 | ||||
| -rw-r--r-- | sql/item.cc | 1 | ||||
| -rw-r--r-- | sql/item.h | 18 | ||||
| -rw-r--r-- | sql/sp_head.cc | 23 |
5 files changed, 91 insertions, 4 deletions
diff --git a/mysql-test/r/sp.result b/mysql-test/r/sp.result index d1d41035475..1570f2252ec 100644 --- a/mysql-test/r/sp.result +++ b/mysql-test/r/sp.result @@ -3166,4 +3166,23 @@ a 4 truncate t2| drop procedure if exists bug12168| +drop table if exists t3| +drop procedure if exists bug11333| +create table t3 (c1 char(128))| +insert into t3 values +('AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA')| +create procedure bug11333(i int) +begin +declare tmp varchar(128); +set @x = 0; +repeat +select c1 into tmp from t3 +where c1 = 'AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA'; +set @x = @x + 1; +until @x >= i +end repeat; +end| +call bug11333(10)| +drop procedure bug11333| +drop table t3| drop table t1,t2; diff --git a/mysql-test/t/sp.test b/mysql-test/t/sp.test index f3e7c3e07a0..6f79243a2b1 100644 --- a/mysql-test/t/sp.test +++ b/mysql-test/t/sp.test @@ -3996,6 +3996,40 @@ truncate t2| drop procedure if exists bug12168| # +# Bug #11333 "Stored Procedure: Memory blow up on repeated SELECT ... INTO +# query" +# One more memleak bug. Use the test to check memory consumption. +# + +--disable_warnings +drop table if exists t3| +drop procedure if exists bug11333| +--enable_warnings + +create table t3 (c1 char(128))| + +insert into t3 values + ('AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA')| + + +create procedure bug11333(i int) +begin + declare tmp varchar(128); + set @x = 0; + repeat + select c1 into tmp from t3 + where c1 = 'AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA'; + set @x = @x + 1; + until @x >= i + end repeat; +end| + +call bug11333(10)| + +drop procedure bug11333| +drop table t3| + +# # BUG#NNNN: New bug synopsis # #--disable_warnings diff --git a/sql/item.cc b/sql/item.cc index 7575a6a218b..98caf4918ab 100644 --- a/sql/item.cc +++ b/sql/item.cc @@ -303,6 +303,7 @@ void *Item::operator new(size_t size, Item *reuse, uint *rsize) if (rsize) (*rsize)= reuse->rsize; reuse->cleanup(); + delete reuse; TRASH((void *)reuse, size); return (void *)reuse; } diff --git a/sql/item.h b/sql/item.h index 4dfd99e0dbd..51f7c641de1 100644 --- a/sql/item.h +++ b/sql/item.h @@ -1298,6 +1298,15 @@ public: // it is constant => can be used without fix_fields (and frequently used) fixed= 1; } + /* Just create an item and do not fill string representation */ + Item_string(CHARSET_INFO *cs, Derivation dv= DERIVATION_COERCIBLE) + { + collation.set(cs, dv); + max_length= 0; + set_name(NULL, 0, cs); + decimals= NOT_FIXED_DEC; + fixed= 1; + } Item_string(const char *name_par, const char *str, uint length, CHARSET_INFO *cs, Derivation dv= DERIVATION_COERCIBLE) { @@ -1309,6 +1318,15 @@ public: // it is constant => can be used without fix_fields (and frequently used) fixed= 1; } + /* + This is used in stored procedures to avoid memory leaks and + does a deep copy of its argument. + */ + void set_str_with_copy(const char *str_arg, uint length_arg) + { + str_value.copy(str_arg, length_arg, collation.collation); + max_length= str_value.numchars() * collation.collation->mbmaxlen; + } enum Type type() const { return STRING_ITEM; } double val_real(); longlong val_int(); diff --git a/sql/sp_head.cc b/sql/sp_head.cc index f119ef1ec22..0a3521e8855 100644 --- a/sql/sp_head.cc +++ b/sql/sp_head.cc @@ -249,10 +249,25 @@ sp_eval_func_item(THD *thd, Item **it_addr, enum enum_field_types type, DBUG_PRINT("info",("default result: %*s", s->length(), s->c_ptr_quick())); CREATE_ON_CALLERS_ARENA(it= new(reuse, &rsize) - Item_string(thd->strmake(s->ptr(), - s->length()), s->length(), - it->collation.collation), - use_callers_arena, &backup_current_arena); + Item_string(it->collation.collation), + use_callers_arena, &backup_current_arena); + /* + We have to use special constructor and allocate string + on system heap here. This is because usual Item_string + constructor would allocate memory in the callers arena. + This would lead to the memory leak in SP loops. + See Bug #11333 "Stored Procedure: Memory blow up on + repeated SELECT ... INTO query" for sample of such SP. + TODO: Usage of the system heap gives significant overhead, + however usual "reuse" mechanism does not work here, as + Item_string has no max size. That is, if we have a loop, which + has string variable with constantly increasing size, we would have + to allocate new pieces of memory again and again on each iteration. + In future we should probably reserve some area of memory for + not-very-large strings and reuse it. But for large strings + we would have to use system heap anyway. + */ + ((Item_string*) it)->set_str_with_copy(s->ptr(), s->length()); } break; } |