Hi,
I have a few doubt here :
1) I want to run a 3 different 'C' programs in same session simulteneously (parelelly). if I make a shell, it is running one after another, I mean it shout run in 3 processors.
2) In 'C' program, how can I assing a value of the unix commant
cat a.txt|wc... (1 Reply)
Hi,
Can anyone tell me the correct answers for these:
1. You have 4 instances running on the same UNIX box. How can you determine which shared memory and semaphores are associated with which instance?
2. How do you increase the OS limitation for open files (LINUX and/or Solaris)?
Thanks:p (1 Reply)
As all of you know whenever a program "say a.c" is complied in linux using the gcc or the cc compiler..it shows the list of errors ( if the program contains any).. i want to modify the compier script so as to list the no of errors only and not the description about the error..like" parse error " ... (1 Reply)
Hello All,
I am very new to UNIX. Please help me to find answers of below questions.
1.A script is saved with name ls. When we execute the script what it will execute?
a) Will execute ls command
b) Will execute the script
c) Will execute script or command depends on the path
... (2 Replies)
Discussion started by: aswathy
2 Replies
5. Forum Support Area for Unregistered Users & Account Problems
How to post a new thread (Regarding Unix related doubts) in Unix Forums.
I registered my id but I am unable to post my Questions to Forum.
Thanks & Regards,
indusri (1 Reply)
Hi all,
I have few question related to Unix environment and commands :
1. what is .chrc file contain and if it is not present then what happens.
2. what is .login file contain,in which dir it is present and what all other uses are their for this file
3. how and who calls .profile when you... (2 Replies)
Hello All,
I am working in a reputed software firm,currently working on testing platform (manual and automation).But I am very much intersted in unix and shell scripting,I feel that I am good at beginner level of shell scripting,still I want to practise shell scripting to become excel in it.I... (1 Reply)
1) I have to create 3 scripts which create different output files. Script one creates datafiles, script2 creates control files and script3 creates flg files. The business wants the same timestamp to be attached to all the files created by these scripts.
Script1- Create data files - Data files... (2 Replies)
Discussion started by: Maya_Pillai
2 Replies
LEARN ABOUT DEBIAN
bup-margin
bup-margin(1) General Commands Manual bup-margin(1)NAME
bup-margin - figure out your deduplication safety margin
SYNOPSIS
bup margin [options...]
DESCRIPTION
bup margin iterates through all objects in your bup repository, calculating the largest number of prefix bits shared between any two
entries. This number, n, identifies the longest subset of SHA-1 you could use and still encounter a collision between your object ids.
For example, one system that was tested had a collection of 11 million objects (70 GB), and bup margin returned 45. That means a 46-bit
hash would be sufficient to avoid all collisions among that set of objects; each object in that repository could be uniquely identified by
its first 46 bits.
The number of bits needed seems to increase by about 1 or 2 for every doubling of the number of objects. Since SHA-1 hashes have 160 bits,
that leaves 115 bits of margin. Of course, because SHA-1 hashes are essentially random, it's theoretically possible to use many more bits
with far fewer objects.
If you're paranoid about the possibility of SHA-1 collisions, you can monitor your repository by running bup margin occasionally to see if
you're getting dangerously close to 160 bits.
OPTIONS --predict
Guess the offset into each index file where a particular object will appear, and report the maximum deviation of the correct answer
from the guess. This is potentially useful for tuning an interpolation search algorithm.
--ignore-midx
don't use .midx files, use only .idx files. This is only really useful when used with --predict.
EXAMPLE
$ bup margin
Reading indexes: 100.00% (1612581/1612581), done.
40
40 matching prefix bits
1.94 bits per doubling
120 bits (61.86 doublings) remaining
4.19338e+18 times larger is possible
Everyone on earth could have 625878182 data sets
like yours, all in one repository, and we would
expect 1 object collision.
$ bup margin --predict
PackIdxList: using 1 index.
Reading indexes: 100.00% (1612581/1612581), done.
915 of 1612581 (0.057%)
SEE ALSO bup-midx(1), bup-save(1)BUP
Part of the bup(1) suite.
AUTHORS
Avery Pennarun <apenwarr@gmail.com>.
Bup unknown-bup-margin(1)