Visit Our UNIX and Linux User Community

Linux and UNIX Man Pages

Test Your Knowledge in Computers #569
Difficulty: Medium
foreach loops are considered syntactic sugar.
True or False?
Linux & Unix Commands - Search Man Pages

trace_block_split(9) [centos man page]

TRACE_BLOCK_SPLIT(9)						     Block IO						      TRACE_BLOCK_SPLIT(9)

NAME
trace_block_split - split a single bio struct into two bio structs SYNOPSIS
void trace_block_split(struct request_queue * q, struct bio * bio, unsigned int new_sector); ARGUMENTS
q queue containing the bio bio block operation being split new_sector The starting sector for the new bio DESCRIPTION
The bio request bio in request queue q needs to be split into two bio requests. The newly created bio request starts at new_sector. This split may be required due to hardware limitation such as operation crossing device boundaries in a RAID system. AUTHORS
Jason Baron <jbaron@redhat.com> Author. William Cohen <wcohen@redhat.com> Author. COPYRIGHT
Kernel Hackers Manual 3.10 June 2014 TRACE_BLOCK_SPLIT(9)

Check Out this Related Man Page

PROBE::IOBLOCK_TRACE(3stap)				  IO Scheduler and block IO Taps			       PROBE::IOBLOCK_TRACE(3stap)

NAME
probe::ioblock_trace.end - Fires whenever a block I/O transfer is complete. SYNOPSIS
ioblock_trace.end VALUES
None DESCRIPTION
name - name of the probe point q - request queue on which this bio was queued. devname - block device name ino - i-node number of the mapped file bytes_done - number of bytes transferred sector - beginning sector for the entire bio flags - see below BIO_UPTODATE 0 ok after I/O completion BIO_RW_BLOCK 1 RW_AHEAD set, and read/write would block BIO_EOF 2 out-out-bounds error BIO_SEG_VALID 3 nr_hw_seg valid BIO_CLONED 4 doesn't own data BIO_BOUNCED 5 bio is a bounce bio BIO_USER_MAPPED 6 contains user pages BIO_EOPNOTSUPP 7 not supported rw - binary trace for read/write request vcnt - bio vector count which represents number of array element (page, offset, length) which makes up this I/O request idx - offset into the bio vector array phys_segments - number of segments in this bio after physical address coalescing is performed. size - total size in bytes bdev - target block device bdev_contains - points to the device object which contains the partition (when bio structure represents a partition) p_start_sect - points to the start sector of the partition structure of the device CONTEXT
The process signals the transfer is done. SystemTap Tapset Reference June 2014 PROBE::IOBLOCK_TRACE(3stap)

15 More Discussions You Might Find Interesting

1. Fedora

Is UNIX an open source OS ?

Hi everyone, I know the following questions are noobish questions but I am asking them because I am confused about the basics of history behind UNIX and LINUX. Ok onto business, my questions are-: Was/Is UNIX ever an open source operating system ? If UNIX was... (21 Replies)
Discussion started by: sreyan32
21 Replies

2. UNIX for Beginners Questions & Answers

Weird 'find' results

Hello and thanks in advance for any help anyone can offer me I'm trying to learn the find command and thought I was understanding it... Apparently I was wrong. I was doing compound searches and I started getting weird results with the -size test. I was trying to do a search on a 1G file owned by... (14 Replies)
Discussion started by: bodisha
14 Replies

3. UNIX for Beginners Questions & Answers

Set hard block limit for user using quota

hi all, i have installed quota on my centos 7 machine and its what im after (setting size limit on users, so they cant fill the hard drive) i want to now make this part of my create user script for my sftp server so i want to do a echo and a read command so i capture the limit they enter... (0 Replies)
Discussion started by: robertkwild
0 Replies

4. UNIX for Beginners Questions & Answers

Best performance UNIX just for HOST Virtualization?

Hi everybody, Which Unix base OS have best performance for HOST virtualization? I tested SmartOS but it needs another OS to connect remotely! Thanks in advance. (11 Replies)
Discussion started by: mbzadegan
11 Replies

5. UNIX for Beginners Questions & Answers

How to increment version inside a file?

Hi All, I need to write a shell script which opens a file and increments the version(text) within the file every time the script runs. For example: $ cat docker_file.yml version: '3.1' services: ui: image: repo-srv.dev.io:5000/facebook/ui:0.0.2-QA1 $ So, I would like... (6 Replies)
Discussion started by: akshayupadhayay
6 Replies

6. Programming

DB2 convert digits to binary format

Dear Team We use DB2 v10.5 and using DBArtisan tool Can someone please guide how to convert digits to binary numbers using db2 feature. Ex> for number 9 , binary should be 1001 ( 8+1) Any help appreciated. Thanks (2 Replies)
Discussion started by: Perlbaby
2 Replies

7. UNIX for Advanced & Expert Users

Tar Command

hi folks, how to using tar with exclude directory and compress it using tar.Z i only know how to exclude dir only with this command below: tar -cvf /varios/restore/test.tar -X excludefile.txt /jfma/test1/ how to compress it using 1 command? Thanx Please use CODE tags as... (6 Replies)
Discussion started by: only
6 Replies

8. UNIX for Advanced & Expert Users

CentOS7 restoring file capabilities

Quite an obscure question I think. We have a rebuild process for remote sites that allows us to PXE rebuild a till (actually a PC with a touch screen and various fancy bits) running CentOS. The current CentOS5 tills work just fine with a tar image restore and some personalisation. Sadly,... (4 Replies)
Discussion started by: rbatte1
4 Replies

9. Docker

Docker learning Phase-I

Hello All, I had recently learnt a bit of Docker(which provides containerization process). Here are some of my learning points from it. Let us start first with very basic question: What is Docker: Docker is a platform for sysadmins and developers to DEPLOY, DEVELOP and RUN applications ... (7 Replies)
Discussion started by: RavinderSingh13
7 Replies

10. UNIX for Advanced & Expert Users

Shopt -s histappend

What is the point of this? Whenever I close my shell it appends to the history file without adding this. I have never seen it overwrite my history file. # When the shell exits, append to the history file instead of overwriting it shopt -s histappend (3 Replies)
Discussion started by: cokedude
3 Replies

11. UNIX for Beginners Questions & Answers

Unsure why access time on a directory change isn't changing

Hello... And thanks in advance for any help anyone can offer me I was trying to work out the differences between displaying modify, access, and change times with the 'ls' command. Everything seems in order when I look at files, but the access time on a directory doesn't seem to change when I... (4 Replies)
Discussion started by: bodisha
4 Replies

12. UNIX for Beginners Questions & Answers

CentOS 6 ran out of space, need to reclaim it

Hello everyone, I am having an issue here with CentOS release 6.6 (Final) that shows all of the space used up, but I can't tell where the space went. Seemingly I am using up 100%, according to df -h Filesystem Size Used Avail Use% Mounted on... (27 Replies)
Discussion started by: DannyBoyCentOS
27 Replies

13. Shell Programming and Scripting

Controlling user input

I'm trying to use a bash script for a psych experiment that involves listening to sound files and responding. If I have something like the code below, how can I make sure that a key press is assigned to RESPONSE only after the second echo statement? for i in 1 2 3; do echo "Ready?" sleep 2 ... (10 Replies)
Discussion started by: darwin_886
10 Replies

14. Shell Programming and Scripting

[TIP] Processing YAML files with yq

After the success of the jq - tool for parsing and manipulating JSON-Data someone wrote a tool called yq, which aims to be the same for YAML, what jq is for JSON. Seems to work fine. I'll definitely give it a chance in future. Example YAML-File: --- !ruby/object:Puppet::Node::Facts ... (1 Reply)
Discussion started by: stomp
1 Replies

15. What is on Your Mind?

Please Welcome Dave Munro to the Moderator Team!

Dear All, I am very pleased to announce that Dave Munro (gull04) is joining the Moderation Team, after being a very valuable member of UNIX.com for 15+ years. Dave is an IT Consultant with 30 years of experience this year, has worked in many of the industry vertical market segments and has... (6 Replies)
Discussion started by: Neo
6 Replies

Featured Tech Videos