On 14 Jun 2018, at 8:33am, x <tam118...@hotmail.com> wrote: > Could someone describe what the return values real, user and sys mean and why > there’s sometimes a big difference between real and the sum of user & sys?.
[The following is simplified for clarity.] 'real' -- Elapsed time between the start and end of the command, as measured by the clock on your wall. Sometimes called 'wall time'. The other two figures both concern just the process you're interested in, ignoring the many other things the computer is doing at the same time like seeing if you've clicked your mouse, updating your screen, checking to see if your laptop battery is going to run out, etc.. 'user' -- Processor time taken by the command itself. If you look at all the source code for that command, this is the time taken to run that source code. 'sys' -- Processor time taken to execute the system calls the command used. If the command used system calls to find the current time, allocate memory, and write some bytes to a file, the amount of time each system call took contributes to 'sys', not 'user'. If 'sys' + 'user' > 'real', something weird happened. If 'sys' + 'user' < 'real', your computer is busy doing a lot of stuff in the background. You probably have a printer plugged in, an ethernet or WiFi connection active, a keyboard and mouse pointer being monitored, etc.. This is normal on a modern computer, Simon. _______________________________________________ sqlite-users mailing list sqlite-users@mailinglists.sqlite.org http://mailinglists.sqlite.org/cgi-bin/mailman/listinfo/sqlite-users