> Gunzip process stalling after every 1 min , [...]

   I don't know what that means.  I don't know what you did.  I don't
know what happened when you did it.  As usual, showing actual commands
with their actual output can be more helpful than vague descriptions or
interpretations.

   Are you trying to expand some file?  How big is this file?  Which
version of gunzip?

> We run a sleep of 5 sec to check the progress.

   This also tells me approxmately nothing.  What, exactly, are you
putting to sleep?  How, exactly, do you "check the progress"?  Define
"progress".

> It stalls for almost after every 45 sec .

   Huh?