Anyone here knows any reasonably priced courses for independent (not corporate) users that can point me to. Already know Unix commands/vi/etc but now need scripting too. Any replies will be appreciated. (2 Replies)
Please Let me know this Que and Ans please Because i applied for a H1B VISA nad i have a INTERVIEW as soon so please "Difference between Linux and Unix and also C and C++ and also about Shell Scripting about all Questions and Answers ." (3 Replies)
I want to learn Linux/Unix shell scripting, I searched this forum but got some results for Unix Admin books and general Linux books.
Would someone recommend a good Linux Shell Scripting book?
I did order one book
A Practical Guide to Linux(R) Commands, Editors, and Shell Programming ... (4 Replies)
In shell Can I pass " to a program ? If not what is the work around ..?
Can I define * as a wild card charecter that will return all the values from
the files ..?
I am trying to create a tool that will return the values from a property file . This tool has to support all the wild card... (1 Reply)
Hi,
I have general question: i have good working Perl script with .pl extension, and now I have to migrate all to another Linux box, and I was told that I can use only shell scripting, so I'm not sure how different those two things are, will it work without any changes . Is there anything smart I... (6 Replies)
hi
My script as below
#!/bin/ksh
for i in `seq 1 7`
do
a=$(awk '{print $i}' /home/rama/expenese.txt)
done
for i in `seq 1 7`
do
echo "${a}"
done
content of expense.txt is as below
5032 210179 3110 132813874 53488966 11459221 5300794
I want output as... (6 Replies)
Use and complete the template provided. The entire template must be completed. If you don't, your post may be deleted!
1. The problem statement, all variables and given/known data:
This is what is asked:
If the user enters ‘3’, prompt the user for two file names. Verify that the file names... (2 Replies)
This is the sample json I have pasted here. I want all the IP address strings to be converted into an array. For example "10.38.32.202" has to be converted to everywhere in the JSON. There are multiple IPs in a JSON I am pasting one sample object from the JSON. But the IPs already in an Array... (11 Replies)
Hi,
I would like to know how to define the size of the array in c shell scripting. (15 Replies)
Discussion started by: gopishrine
15 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)