php - symfony2 session persistance -

this has been bugging me week now.

i cant seem large php array persist in session on page redirect.

for ($i=1;$i<$data['weeks'];$i++) {     $instances[] = array(         'start' => $starttime + ((86400 * 7) * $i),         'end'   => $starttime + ((86400 * 7) * $i) + $duration,         'venueid' => $data['venueid']     ); }  $request->getsession()->set('addclass-1-instances', $instances);  return new redirectresponse ($this->generateurl(     'class_add', array(         'clubid' => $this->club->clubid,         'step' => 4,         'classtype' => 1     ) )); 

this works when array small (1-10 elements) fails when larger (1000 - 2000 elements).

if dump out session object after adding it, can see in session attributes collection.

var_dump($request->getsession());  protected 'attributes' => &     array (size=6)         'addclass-1-instances' =>              array (size=1560)                 0 => ... 

but once page redirected, session appears totally empty.

object(symfony\component\httpfoundation\session\attribute\attributebag)[487]     private 'name' => string 'attributes' (length=10)     private 'storagekey' => string '_sf2_attributes' (length=15)     protected 'attributes' => &         array (size=0)             empty 

we store our sessions in database, , works fine throughout rest of webapp. i've read on place , seen people talk session.save-dir php option, not right think irrelevant when using db storage.

help!

not sure how solve this. session ids remain same on both pages, , theres no code explicitly clears session.

not sure go not here!