Operating Systems · Previous year questions
File Systems, I/O and Disk Scheduling
20 questions from GATE CS 2011 to 2026, newest first.
Questions
GATE CS 2026 Set 1, Q.59
Consider a hard disk with a rotational speed of rpm. The time to move the read/write head from a track to its adjacent track is millisecond. Initially, the head is o...
File Systems, I/O and Disk Scheduling
GATE CS 2026 Set 2, Q.53
To keep track of free blocks in a file system, one of the two approaches is generally used - using bitmaps (bit vectors) or using linked lists. Consider that the linked list app...
File Systems, I/O and Disk Scheduling
GATE CS 2025 Set 1, Q.51
A disk of size 512M bytes is divided into blocks of 64K bytes. A file is stored in the disk using linked allocation. In linked allocation, each data block reserves 4 bytes to st...
File Systems, I/O and Disk Scheduling
GATE CS 2024 Set 1, Q.54
Consider a 512 GB hard disk with 32 storage surfaces. There are 4096 sectors per track and each sector holds 1024 bytes of data. The number of cylinders in the hard disk is ____...
Memory Hierarchy: Cache, Main Memory and Secondary Storage · File Systems, I/O and Disk Scheduling
GATE CS 2024 Set 2, Q.53
Consider a disk with the following specifications: rotation speed of 6000 RPM, average seek time of 5 milliseconds, 500 sectors/track, 512-byte sectors. A file has content store...
File Systems, I/O and Disk Scheduling · I/O Interface, Interrupts and DMA
GATE CS 2022, Q.63
Consider two files systems A and B, that use contiguous allocation and linked allocation, respectively. A file of size 100 blocks is already stored in A and also in B. Now, cons...
File Systems, I/O and Disk Scheduling
GATE CS 2021 Set 1, Q.25 (CS Q.15)
Consider a linear list based directory implementation in a file system. Each directory is a list of nodes, where each node contains the file name along with the file metadata, s...
File Systems, I/O and Disk Scheduling
GATE CS 2020, Q.45 (CS Q.35)
Consider the following five disk access requests of the form (request id, cylinder number) that are present in the disk scheduler queue at a given time.…
File Systems, I/O and Disk Scheduling
GATE CS 2019, Q.52 (CS Q.42)
The index node (inode) of a Unix-like file system has 12 direct, one single-indirect and one double-indirect pointers. The disk block size is , and the disk block a...
File Systems, I/O and Disk Scheduling
GATE CS 2018, Q.63 (CS Q.53)
Consider a storage disk with 4 platters (numbered as 0, 1, 2 and 3), 200 cylinders (numbered as 0, 1, … , 199), and 256 sectors per track (numbered as 0, 1, … , 255). The follow...
File Systems, I/O and Disk Scheduling
GATE CS 2017 Set 2, Q.8 (CS Q.8)
In a file allocation system, which of the following allocation scheme(s) can be used if no external fragmentation is allowed? I. Contiguous II. Linked III. Indexed
File Systems, I/O and Disk Scheduling
GATE CS 2016 Set 1, Q.58 (CS Q.48)
Consider a disk queue with requests for I/O to blocks on cylinders 47, 38, 121, 191, 87, 11, 92, 10. The C-LOOK scheduling algorithm is used. The head is initially at cylinder n...
File Systems, I/O and Disk Scheduling
GATE CS 2016 Set 2, Q.60 (CS Q.50)
A file system uses an in-memory cache to cache disk blocks. The miss rate of the cache is shown in the figure. The latency to read a block from the cache is 1 ms and to read a b...
File Systems, I/O and Disk Scheduling · Memory Hierarchy: Cache, Main Memory and Secondary Storage
GATE CS 2015 Set 1, Q.40 (CS Q.30)
Suppose the following disk request sequence (track numbers) for a disk with tracks is given: . Assume that the initial position of the...
File Systems, I/O and Disk Scheduling
GATE CS 2015 Set 2, Q.59 (CS Q.49)
Consider a typical disk that rotates at 15000 rotations per minute (RPM) and has a transfer rate of bytes/sec. If the average seek time of the disk is twice the...
File Systems, I/O and Disk Scheduling
GATE CS 2014 Set 1, Q.29 (CS Q.19)
Suppose a disk has 201 cylinders, numbered from 0 to 200. At some time the disk arm is at cylinder 100, and there is a queue of disk access requests for cylinders 30, 85, 90, 10...
File Systems, I/O and Disk Scheduling
GATE CS 2014 Set 2, Q.30 (CS Q.20)
A FAT (file allocation table) based file system is being used and the total overhead of each entry in the FAT is 4 bytes in size. Given a bytes disk on which t...
File Systems, I/O and Disk Scheduling
GATE CS 2013, Q.29 (CS Q.29)
Consider a hard disk with 16 recording surfaces (0-15) having 16384 cylinders (0-16383) and each cylinder contains 64 sectors (0-63). Data storage capacity in each sector is 512...
File Systems, I/O and Disk Scheduling
GATE CS 2012, Q.41 (CS Q.41)
A file system with 300 GByte disk uses a file descriptor with 8 direct block addresses, 1 indirect block address and 1 doubly indirect block address. The size of each disk block...
File Systems, I/O and Disk Scheduling
GATE CS 2011, Q.44 (CS Q.44)
An application loads 100 libraries at startup. Loading each library requires exactly one disk access. The seek time of the disk to a random location is given as 10 ms. Rotationa...
File Systems, I/O and Disk Scheduling