Guys need some advice on how to check some of the questions below?
i'm running on an open VMS platform... which i am an idiot to...
appreciate if anyone can give some hints or source on how to check on..
a script that is running on cron job... but doesn't run as the login user name..
1. why... (6 Replies)
Query 1 : How to check if a directory already exists? If doesn't exist then
create a new one.
Query 2 : I want to put following text using a single echo statement into a
log file and also want to retain the formatting of the text. How it
can be... (3 Replies)
hi guys
Well, i need to have a report generation script or any script which will show me all the content/information of a file when i run that script.
Please help me on this isssue at the earliest.As i am little bit aware of scripting.Thanks in advance!
regards
ash (4 Replies)
Any help on like where to get started on this? I'm just confused.
1. The problem statement, all variables and given/known data:
Enter text here.Queries to satisfy these two report requests (use your CCI database):
Retrieve all rows of active inventory where current on hands is less than... (0 Replies)
Hi,
First query:
I am trying to execute the below command to pull all the record whose length is not of the expected. But this is not giving the expected results.
$2 is the record length passed in the script as second parameter.$filename is the filename on which the awk is executed.It is... (4 Replies)
Is there any way to see how many queries come into our external DNS server? In looking at DNS providers, most of them base pricing on number of queries per month so I just wanted to see if you had any idea/way of gathering that data? A rough ballpark figure would even work.
Our DNS server is... (1 Reply)
Hi,
1) How to get exact permissions, group names for files while transferring with FTP
2) Is there any command to transfer entire directory and sub directories.
Thanks (1 Reply)
Hello,
I am posting the following questions here because I need them answered by people who have actually done a lot of work in GRUB. DO NOT GIVE ME GUESS ANSWERS PLEASE. Feel free to redirect me if this is not the right place to ask these questions.
Can I download GRUB separately from... (6 Replies)
Hey everyone,
I have a question, I've been playing around with tcpdump, and noticed my machine making numerous rdns look ups. They are displayed like:
10.80.80.141.51234 > 10.80.80.1.domain: 9950+ PTR? 223.114.55.65.in-addr.arpa. (44)
My question is, if dns works based on numerical... (0 Replies)
Discussion started by: Lost in Cyberia
0 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)