Another nice thing about /usr/bin/time is the --verbose flag which gives:

  Command being timed: "ls"
  User time (seconds): 0.00
  System time (seconds): 0.00
  Percent of CPU this job got: 0%
  Elapsed (wall clock) time (h:mm:ss or m:ss): 0:00.00
  Average shared text size (kbytes): 0
  Average unshared data size (kbytes): 0
  Average stack size (kbytes): 0
  Average total size (kbytes): 0
  Maximum resident set size (kbytes): 1912
  Average resident set size (kbytes): 0
  Major (requiring I/O) page faults: 0
  Minor (reclaiming a frame) page faults: 112
  Voluntary context switches: 1
  Involuntary context switches: 1
  Swaps: 0
  File system inputs: 0
  File system outputs: 0
  Socket messages sent: 0
  Socket messages received: 0
  Signals delivered: 0
  Page size (bytes): 4096
  Exit status: 0