3 move info from Ajasja's comment. edited Mar 21 '13 at 20:39 rm -rf♦ 81.8k1919 gold badges256256 silver badges414414 bronze badges Have you tried setting $HistoryLength to zero: $HistoryLength=0;  The memory is not freed, because the previous data is still available by Out[nn] or %nn. Note that if you do this, using %, %%, %n etc., which some people use in example code will not work. And when a large data set is shown the "Show More" and "Show Less" buttons do not work. You can bypass both problems by setting $HistoryLength to 1 while still conserving a lot of memory. Have you tried setting $HistoryLength to zero: $HistoryLength=0;  The memory is not freed, because the previous data is still available by Out[nn] or %nn. Have you tried setting $HistoryLength to zero: $HistoryLength=0;  The memory is not freed, because the previous data is still available by Out[nn] or %nn. Note that if you do this, using %, %%, %n etc., which some people use in example code will not work. And when a large data set is shown the "Show More" and "Show Less" buttons do not work. You can bypass both problems by setting $HistoryLength to 1 while still conserving a lot of memory. 2 added 8 characters in body edited Apr 16 '12 at 21:45 rm -rf♦ 81.8k1919 gold badges256256 silver badges414414 bronze badges Have you tried setting $HistoryLength$HistoryLength to zero: $HistoryLength=0;  The memory is not freed, because the previous data is still available by Out[nn]Out[nn] or %%nn. Have you tried setting$HistoryLength to zero: $HistoryLength=0;  The memory is not freed, because the previous data is still available by Out[nn] or %. Have you tried setting $HistoryLength to zero: $HistoryLength=0;  The memory is not freed, because the previous data is still available by Out[nn] or %nn. 1 answered Apr 16 '12 at 21:37 Ajasja 9,86422 gold badges3838 silver badges9797 bronze badges Have you tried setting$HistoryLength to zero: \$HistoryLength=0;  The memory is not freed, because the previous data is still available by Out[nn] or %.