[ruby-core:23969] Re: [Bug #1677] memory leak in DBD-mysql

2009/6/22 Qi Lu <[e-mail]>:
> Bug #1677: memory leak in DBD-mysql
> http://redmine.ruby-lang.org/issues/show/1677
>
> Author: Qi Lu
> Status: Open, Priority: Normal
> ruby -v: 1.8.6
>
> I found a serious memory leak in my Ruby code, then I narrow it down and =
found that there is leak in dbd-mysql. The ruby version is 1.8.6 and dbd-my=
sql is 0.4.2. it wrote a test code and run in windows XP/Vista/2003, it lea=
ks in all OS, about 3M/day. Here is my test code:
>
> require 'dbi'
>
> connection =3D DBI.connect("DBI:Mysql:localhost;database=3Dleaktest;port=
=3D3306, leaktest, kael4")
>
> i =3D 1
> name =3D 'test'
> while true do
> =C2=A0value =3D name + i.to_s
> =C2=A0sql =3D "insert into test (name) values ('#{value}');"
> =C2=A0sth =3D connection.execute(sql)
> =C2=A0sleep 0.5
> =C2=A0sth.finish
> =C2=A0sleep 0.5
> =C2=A0i +=3D 1
> end
>
> make sure to setup database, here are the statement:
>
> mysql> create database leaktest;
> mysql> create table test ( ID int(11) NOT NULL auto_increment, name varch=
ar(20) not nul
> l, CONSTRAINT PK_test_id PRIMARY KEY (ID) );
> mysql> grant select,update,insert,delete,execute,create,drop,alter on Sky=
Msgs.* to SkyM
> sgs@localhost identified by 'MsgsSky';
>
> This test only do simply insertion operation in MySQL.
>
I have no idea about the memory leak in this case. Just an advice.
Since your code is processing statements that return no result set,
sth.finish is meaning less. You should use #do instead of #execute
like this:

 while true do
  value =3D name + i.to_s
  sql =3D "insert into test (name) values ('#{value}');"
  connection.do(sql)
  sleep 1
  i +=3D 1
 end

Regards,

Park Heesob