The difference between user time and sys time

[Singaram]

I have two version on the program.
When i run them the new version runs very slow.
When i time it the sys time shows the same for both but the user time is more in the newer version.

On what reasons the user time is more than the sys time?.

Thanks
Singaram

[Sridhar Bhaskarla]

Hi,

User Time: the time CPU spent in user mode.
System Time: time CPU spent in running system calls.

User time is basically to run the the code like computations etc., that run directly using the CPU's built-in instructions. System time is when the user code uses the system calls like reading from the input, writing to a disk etc.,

Increase in the user time may be an indication of poorly written code if there isn't enhanced functionality for the application.

-Sri