Limit PFC WD Detection time to maximum value of 1000[ms]

[dprital]

What I did

PFC WD Detection time is defined by the following calculation:

DEFAULT_POLL_INTERVAL * multiply

where:

• multiply = max(1, (port_num-1)//DEFAULT_PORT_NUM+1)
• port_num = len(list(self.config_db.get_table('PORT').keys()))
• DEFAULT_POLL_INTERVAL = 200
• DEFAULT_PORT_NUM = 32

There is an allowed range for this value which is between 100..3000 [ms].
For system with more than 448 ports, we will violate this range.

In addition, there is no meaning to have detection time of more than 1000[ms], hence, this change limit the maximum detection time for PFC WD to 1000[ms]

How I did it

Calculate PFC WD Detection time, if it become bigger than 1000[ms], set it to 1000[ms]

How to verify it

Run PFC WD Tests on several platforms

Previous command output (if the output of a command-line utility has changed)

New command output (if the output of a command-line utility has changed)

[stephenxs]

LGTM but I think we still need to confirm the performance on tigon

[stephenxs]

Do you want to add UT?