Hi,

 

why concating blob consume memory and not leave it until transaction end?

 

simple sample

 

SET TERM ^ ;

 

CREATE PROCEDURE TEST_BLOB_CONCAT 

 ( A BLOB SUB_TYPE TEXT, ILE INTEGER ) 

RETURNS 

 ( B BLOB SUB_TYPE TEXT )

AS 

DECLARE VARIABLE VAR_I INTEGER; 

BEGIN

  VAR_I = 0;

  B = 'ABC';

  WHILE (VAR_I<ILE) DO

    BEGIN

      B = B || A;

      VAR_I = VAR_I + 1;

    END

  SUSPEND;

END^

 

SET TERM ; ^

 

/*----------------------------------------------------*/

 

SELECT * FROM TEST_BLOB_CONCAT('', 5000) 

result 'ABC'

 

consume memory 

________used: 12208

_________max: 38112

_____allocated: 65536

_allocatedmax:  65536

 

/*----------------------------------------------------*/

 

SELECT * FROM TEST_BLOB_CONCAT('', 500000) 

result 'ABC'

 

consume memory 

________used: 12208

_________max: 2338208

_____allocated: 2359296

_allocatedmax:  2359296

 

/*----------------------------------------------------*/

 

SELECT * FROM TEST_BLOB_CONCAT('', 50000000) 

result 'ABC'

 

consume memory all memory from operating system!

 

 

It looks like some temp buffers are created and not freed until transaction end

Is this bug reported or i should report it to the tracker?

 

regards,

Karol Bieniaszewski

 

------------------------------------------------------------------------------------------------------------

 

http://tracker.firebirdsql.org/browse/CORE-4671

 

Helen

 

------------------------------------------------------------------------------------------------------------

 

Hi Hellen,

 

it looks like bug is not fixed only minimized?

I test this with current FB3 snapshot.

 

This fix do only something like this

 

previous before fix

1. transaction start

2. Before execute statement memory low

3. memory increases during statement execution

SELECT * FROM TEST_BLOB_CONCAT('', 50000000)

4. after statement is finished memory is still the same

5. commit transaction ->>> memory relased

 

after fix

1. transaction start

2. Before execute statement memory low

3. memory increases during statement execution

SELECT * FROM TEST_BLOB_CONCAT('', 50000000)

4. after statement ->>> memory relased

5. commit transaction

 

I see that this fix - not fix reason of the bug - only minimize it?

Should i post this as new bug into the tracker or put comment there?

 

 

regards,

Karol Bieniaszewski

 

 

 

I resend this from support group as Helen said.

Why temp blobs are not freed immediately and consume resources? 

 

 

regards,

Karol Bieniaszewski