I am sure someone will yell at me over this post, but honestly I have searched. It doesn't help that I am not sure what to search on.
Little background. Working at new company, Company has a program on a Unix box AIX.4. I know virtually nothing about Unix and Neither does anyone else here ... (1 Reply)
Hello,
My first post to the Unix forums, thanks for having me!
The division of the company I work for uses a xseries/redhat/VMWareServer
solution to make sure that we keep hardware overhead low and use our machines to as near capacity as we can. These boxes are Intel with usually
dual or... (1 Reply)
Hello guys, new here so please take it easy on me :-). Here is my issue. We use an application called Medical Manager and it runs on AIX. There is a user that is showing stuck with in the application. However when I try to run any of "ps" commands I don't see it. I need to kill this user and I... (2 Replies)
I need to do a switch user in an automated mode and do a ftp using that switched id.
Scenario:
initial login xx.
switch to user-yy without manually entering the password.
ftp some files from user yy to another user zz - automated mode.
Can any unix experts can help me for my above query? (1 Reply)
Dear Friends ,
I got a problem In our AIX 6.1 server . When I start or restart the machine I cannot Login the server . It shows a dialog box and shows some comments , those are :
>>
The DT messaging system could not be started .
To correct the problem :
1. Choose to return the login... (1 Reply)
Hi all,
I cannt use 'su' to login to root or any other users though everything seems ok. I read some articles that says if you do recursive chmod 777 on /usr it can create this problem.
I did the same. can anybody tell me how to repair it. Any ideas will be appreciated.
thnks (7 Replies)
Hello,
Sorry for my poor English.
I have to reduce rights for a user on AIX system so that:
When he does , he find in output, only filesystems on which he has permissions
.He can't do to change user.
Very thanks for helping. (2 Replies)
Hi,
I want to create a new user,and I want to give read permission to a folder which owned by root.
How can I do this?
thanks for your helps (4 Replies)
Hello,
I am curious that is there a way I can restrict a user or a set of users to execute the C/C++ compiler, basically what I want is to lock it down to a particular user and none of the other users should be able to compile any code.
Thanks in advance. (14 Replies)
Discussion started by: m6248m
14 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)