I want to get a full added amount of memory usage for a particular process. Foe example, say I want to have the total amount of memory taken by httpd. So if I do a tail command as tail -M, I get:  PID USER      PR  NI  VIRT  RES  SHR S %CPU %MEM    TIME+  COMMAND                                                                                 10036 mysql     20   0  417m  76m 3820 S  0.3 15.5   0:13.55 mysqld                                                                                  10453 apache    20   0  229m  67m  42m S  0.0 13.7   0:10.81 httpd                                                                                   10447 apache    20   0  230m  64m  38m S  0.0 13.0   0:11.54 httpd                                                                                   10479 apache    20   0  226m  64m  42m S  0.0 13.0   0:09.75 httpd                                                                                   10478 apache    20   0  230m  63m  38m S  0.0 12.9   0:11.02 httpd                                                                                   10451 apache    20   0  230m  63m  37m S  0.0 12.8   0:10.37 httpd                                                                                    9599 apache    20   0  227m  61m  38m S  0.0 12.4   0:10.80 httpd                                                                                   10454 apache    20   0  226m  60m  38m S  0.0 12.2   0:09.56 httpd                                                                                   10476 apache    20   0  225m  58m  38m S  0.0 11.9   0:09.87 httpd                                                                                   10332 apache    20   0  228m  50m  24m S  0.0 10.2   0:13.73 httpd                                                                                   10445 apache    20   0  220m  42m  24m S  0.0  8.5   0:10.17 httpd                                                                                     637 root      10 -10 32816  25m 1712 S  0.0  5.2   0:00.01 iscsiuio                                                                                  652 root      10 -10  5128 2972 1876 S  0.0  0.6   0:05.86 iscsid                                                                                   9592 root      20   0  207m 2872  900 S  0.0  0.6   0:00.39 httpd                                                                                   10196 nobody    20   0  136m 2408  500 S  0.0  0.5   0:00.79 memcached              In this case I want to have the VIRT, RES, SHR, %CUP, & %MEM totally as added for each rows of the output.Is there anyway I can do that? 
Total amount of memory usage by a single process
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