I/O - Request (Write/Read) - IO Request Packet (IRP)

Card Puncher Data Processing


An I/O request can be intended for any:

IO request occurs per block

I/O operations issued to a driver on behalf of the application.

I/O requests are destined to a device

  • operated by a single-layered driver
  • or reached through a multilayered driver.

I/O request can be synchronous or asynchronous



  • Read
  • Write
  • Others (Control, etc…)


The location of the needed data is given via the offset.

Example: “retrieve 8 block of data starting at offset 8100”.


See IO - Scheduling (disk scheduling)


read and write system call


The I/O request packet (IRP) is where the I/O system stores information it needs to process an I/O request. When a thread calls an I/O API, the I/O manager constructs an IRP to represent the operation as it progresses through the I/O system.


Windows Read

ie CPU

Io Request Lifecycle Windows


Io Printer Lifecyle

Documentation / Reference

Discover More
Card Puncher Data Processing
Computer - Storage Device (Media)

A storage device is a that stores byte: machine instructions byte data byte It is an array of circuits that saves bit state (0 or 1). A storage device can be anything that can store and retrieve...
Card Puncher Data Processing
Data Processing - Buffer (Batch concept in code)

Buffers are catalog containers of a (fixed|variable with max) amount of data or operations. memoryblocksdisk Without buffer, each read or write request is handled directly by the underlying layer (OS,...
Card Puncher Data Processing
Data Storage - The Buffer Cache (File System Cache)

All data accessed from files on the system that are performed through the use of read() and write() system calls, pass through the file system buffer cache. This buffer cache greatly speeds up disk access...
Drive - Hard (disk|drive) (HDD) - Mass Storage - Flash

A disk is a storage device that refers to magnetic media, such as: a floppy disk, the disk in your computer's hard drive, an external hard drive. It's also known as mass storage device. Disks...
Card Puncher Data Processing
I/O - (Input/Output|Read/Write) - Data Access

I/O devices can be interpreted as streams, as they produce or consume potentially unlimited data over time. IO = Input / Output = Writing and Reading data. It's an umbrella term that regroups IO transfer...
Card Puncher Data Processing
IO - Block (Batch on device)

A block is a unit of storage representing a fix number of bytes called the block size. It's also known as the minimum unit of transfer. It implements the concept of batch where data is organized into...
Top Iowait
IO - Metrics (Monitoring|Measurement)

in IO. A collection of IO metrics explained. IO wait is the percentage of time that the CPU waits for the IO request. Example via : IOPS is the number of IO request per second also known as:...
Card Puncher Data Processing
IO - Scheduling (disk scheduling)

Input/output (I/O) scheduling known also as disk scheduling is the method that computer operating systems use to decide in which order the block I/O operations will be submitted to storage volumes. ...
Card Puncher Data Processing
Memory - Physical Address

in computer memory Same as ?? OSvirtual address When storing and retrieving data from memory, an offset is used to determine the location in which the data is stored. This is fixed-length sequences...

Share this page:
Follow us:
Task Runner