I was using XAMPP for my local machine but as I wanted to run applications like mysql work bench and some test frameworks I decided to switch to LAMP self install. I'm using ubuntu and followed the instructions at: https://help.ubuntu.com/community/ApacheMySQLPHP

But the problem is LAMP is consuming too much of my memory (RAM) I've allocated 124 MB currently but still it gives me memory exhausted error when I run Drush (Drupal command line). When I do drush cc to clear cache it give me the following:

    Fatal error: Allowed memory size of 33554432 bytes exhausted (tried to allocate 122880 bytes) in /var/www/----/sites/all/modules/ubercart/uc_order/uc_order.order_pane.inc on line 150

Call Stack:
    0.0020     185624   1. {main}() /opt/drush/drush.php:0
    0.0254    1303672   2. drush_main() /opt/drush/drush.php:37
    0.2674    5107784   3. drush_bootstrap() /opt/drush/drush.php:71
    0.2676    5109872   4. _drush_bootstrap_drupal_full() /opt/drush/includes/environment.inc:173
    0.2676    5151032   5. drupal_bootstrap() /opt/drush/includes/environment.inc:655
    0.3030    7739048   6. _drupal_bootstrap() /var/www/missmoti/includes/bootstrap.inc:989
    0.3122    8855792   7. _drupal_bootstrap_full() /var/www/missmoti/includes/bootstrap.inc:1078
    0.3445   12387320   8. module_load_all() /var/www/missmoti/includes/common.inc:2608
    0.5194   32586544   9. drupal_load() /var/www/missmoti/includes/module.inc:14
    0.5251   33361112  10. include_once('/var/www/missmoti/sites/all/modules/ubercart/uc_order/uc_order.module') /var/www/-----/includes/bootstrap.inc:617

Drush command could not be completed.   

In each error it shows me a back trace and I guess this default debugger I'm not aware of in Apache or my PHP config it eating up the memory. If anyone can help I"d be glad.

Another error below:

    Fatal error: Call to undefined function dsm() in /var/www/-----/sites/all/modules/custom/gtpath/gtpath.module on line 180
Call Stack
#   Time    Memory  Function    Location
1   0.0002  120144  {main}( )   ../index.php:0
2   1.7604  68224112    theme( )    ../index.php:36
3   2.0188  77346112    call_user_func_array ( )    ../theme.inc:658
4   2.0188  77347024    gtpath_preprocess_page( )   ../theme.inc:0

how do I deal with this default debugger? how do I turn it off??