# Help with system in a safe state?

Posted by Lo
Announcements Last Post
SoC Curricula 09/30/2017 01:08PM
Demarcation or scoping of examinations and assessment 02/13/2017 07:59AM
School of Computing Short Learning Programmes 11/24/2014 08:37AM
Unisa contact information 07/28/2011 01:28PM
 Help with system in a safe state? April 03, 2011 12:14AM Registered: 8 years ago Posts: 23 Rating: 0
Hi
Can you please help me out here with how to determine whether a system is in a safe state for Question 1.2 and 1.3 using the steps defined in the book. I do understand what it means for a system to be in safe state it is only the steps that confuses me. I am totally out.
Thanks!
 Re: Help with system in a safe state? April 03, 2011 02:31PM Registered: 10 years ago Posts: 3,496 Rating: 1
Try this smallest-possible-tip for starters, and ask again if it doesn't help. (I don't want to deprive you of the satisfaction of solving it, that's all).

Work == "Available"

(And then run the algorithm with that assumption.)

I'll check the forum again later today if that's utterly useless to you. It was just my own sticking point, that's all.
 Re: Help with system in a safe state? April 04, 2011 03:54PM Registered: 8 years ago Posts: 23 Rating: 0
Hey,
I have taken forever to come back, I have just got into the net. I am trying to make sense with basic clue you gave me together with the info I get from the site "Unisa Chatter-operating system..." I will come back later for the feedback.
Thanks
 Re: Help with system in a safe state? April 04, 2011 04:21PM Registered: 8 years ago Posts: 23 Rating: 0
Am I correct if I get Available = -999, from
1 6 5 0
- 1 6 5 8 and what would be the status of Available being a negative, what about the safe sequence
 Re: Help with system in a safe state? April 04, 2011 04:35PM Registered: 8 years ago Posts: 23 Rating: 0
Please ignore the above 2 posts, I do not know what confused me, I did not use max_resource value.
 Re: Help with system in a safe state? April 04, 2011 04:54PM Registered: 8 years ago Posts: 23 Rating: 0
Am I at the right track if I get Available = (2,8,5,4) for P1
 Re: Help with system in a safe state? April 04, 2011 04:56PM Registered: 10 years ago Posts: 3,496 Rating: 1
Just in case: It's a mistake to think of "1234" as "one thousand two hundred and thirty-four". Rather try "[1,2,3,4]" I think it'll make a lot more sense if you do that.

You're working on a matrix, after all...
 Re: Help with system in a safe state? April 04, 2011 06:13PM Registered: 8 years ago Posts: 23 Rating: 0
I have reworked my sense of understanding and my answers. Please verfy if I am at the correct track now for P0 and P4 Available = [1, 6, 6, 4] and [1, 12, 9, 6] respectively.
 Re: Help with system in a safe state? April 05, 2011 12:26AM Registered: 10 years ago Posts: 3,496 Rating: 1
It's quite possible that you're now on a better track than I was. No offense, but I hope not.

I get a different value for the initial state, so it's no surprise our end states differ.

Probably handing around values would be the kind of thing that leads to us both sharing the mark, but perhaps you could tell me how you're calculating your initial vector? I can't really remember how I did mine (and it's too late if I've got it wrong, because it's already in), but perhaps I can either confirm that you're right (after which I can go somewhere quiet and cry), or pick up where you're going adrift?

At least you're now in vector and matrix form eh? I'm sure that in a pinch they'll give us some marks for that.
Sorry, only registered users may post in this forum.