Hi, 'm trying to do an exercicise, and one part is:
Seek the maximum and minimum size of files that are to implement the command ls-l. The problem is that it shows me the right way to screen the most, but not the least, and more turns that I fail to see what could be the problem.
Thanks
Last edited by Franklin52; 07-26-2009 at 09:08 AM..
Reason: adding code tags
Hello guys..
well, im kinda newbie with unix because i started to learn it like 2 weeks ago.
then i started to make some exercises, but i got stucked on this one :
so, i need to know how many different 'names' has the 5th field and how many times each name appears.
i was trying with a... (6 Replies)
Hello guys.
Well, on this exercise i need the average "chargeAmount" per hour (for each hour).
with this code :
cat getusagesummarywrongmatch | grep -iv MOU2GRTObject | cut -d'|' -f4,14 | grep -i chargeamount | cut -d' ' -f2
http://img227.imageshack.us/img227/5889/65969235do0.jpg
i got... (2 Replies)
you are to write a program which will read in a tax rate (as a percentage) and the prices of 5 items. the program is to calculate the total price, before tax, of the items and then the tax payable on those items, and then the total amount due. the tax payable is computed by appliying the tax rate... (1 Reply)
hello everyone!:)
I have an exercise which I think is difficult for beginner like me. Here is the exercise
Create a shell script, which takes a directory as command line argument.
Script displays ten first lines from every text file in that directory. After
displaying the lines from the... (1 Reply)
Hi,
I have 80 large files, from which I want to get a specific value to run a Bash script. Firstly, I want to get the part of a file which contains this:
Name =A
xxxxxx
yyyyyy
zzzzzz
aaaaaa
bbbbbb
Value = 57
This is necessary because in a file there are written more lines which... (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:
Write a shell script program that will input a name and a mark between 0 and 100. The program then displays the... (9 Replies)
Hi All,
We've a VDI infrastructure in AWS (AWS workspaces) and we're planning to automate the process of provisioning workspaces. Instead of going to GUI console, and launching workspaces by selecting individual users is little time consuming. Thus, I want to create them in bunches from AWS CLI... (6 Replies)
Discussion started by: arun_adm
6 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)