I am using libsandbox and there is this parameter in quota named wallclock.I googled and
found that it means time for which the program was active(ie. the real time displayed
when we do ./a.out running executable of a program).
I am using it for an online judge , so how does the wallclock parameter vary from
program to program.What value should I give to it, and also if this time is exceeded what
error is thrown by the libsandbox.
libsandbox can apply two types of time limit to sandboxed programs, namely, cpu clock quota and wall clock quota. Both can trigger result code TL (time limit exceeded). Literally, cpu clock defines the processor time consumed by the sandboxed program, and wall clock measures the elapsed real-world time since the start of the sandboxed program.
The reason we need wall clock quota is that some programs (e.g. idle programs and I/O-intensive programs) may exhibit slow cpu clock consumption and remain alive for an undesirably long wall clock life time.
The recommended value for wall clock quota is 10x-15x that of the cpu clock quota.
DISCLAIMER: I am the author of libsandbox.