ME test series: OS

Question

My doubt here is can we not use medium term scheduler to swap process in vritual memory to avoid thrashing ?

Comments

$You\ can\ instruct\ MTS\ to\ suspend\ some\ of\ the\ process\ if\ system\ \underline{already}\ in\ thrashing$
Thrashing is a state in which the CPU performs 'productive' work less, and $\underline {swapping}$' more.
I think they might be right, just ignore my last comment !

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Actually in the solution video the faculty says there is no realtionb/w swapping and thrashing, which I think is not the correct reason., And ya i think it should be because of "always".

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May be they are right. Look for the edit one.

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Thrashing is dependent upon howmany memory frames are allocated for that process... If less no.of frames allocated, then it leads to thrashing, for that swapping a process from main memory to secondary memory doesn't help us

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@Shaik Masthan

If less no.of frames allocated, then it leads to thrashing

If we increase the degree of multiprogramming after some extent the CPU utilization will drastically fall down & the system will spent more time only in the $page\ replacement$: thrashing

Sir, what you stated for thrashing and the one which I wrote are both same some how ?

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If you increase the degree of multi programing, it should lead to allocate less no.of frames per process.


But decreasing the DOM doesn't always lead to increase the no.of frames.

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@Shaik Masthan

1. If processes are utilizing all main memory and need additional memory pages, a cascade of severe cache misses known as page faults will occur, often leading to a noticeable lag in operating system responsiveness. This process together with the futile, repetitive page swapping that occurs are known as thrashing.
2. The CPU is busy in swapping pages so much that it can not respond to users programs and interrupts as much as required. Thrashing occurs when there are too many pages in memory, and each page refers to another page.
3. When each page in execution demands that page that is not currently in real memory (RAM) it places some pages on virtual memory and adjusts the required page on RAM. If the CPU is too busy in doing this task, thrashing occurs.

it should lead to allocate less no.of frames per process.
 

After all this does it means that the required number of frames that a process wants, that process is not able to get it because of lot of swapping ??