Hi there,
first of all, here is my conf of a uname -a
Linux SAMBA 2.4.18-4GB #1 Wed Mar 27 13:57:05 UTC 2002 i686 unknown
on a fedora machine.
Here is my problem: every once in a while, the line containing root disappears in the /etc/passwd, disabling all logging on my server. Any one have... (0 Replies)
Can some-one give me a view to this :
I have a directory in an unix server, having permissions r-xr-xr-x .This directory is basically a source directory.
Now there is another directory basically the destination directory which has all the permissions.
Note:I log in as not the owner,but user... (5 Replies)
$ echo a.bc | sed -e "s/\|/\\|/g"
|a|.|b|c|
$
Is the behavior of the sed statement expected ? Or is this a bug in sed ?
OS details
Linux 2.6.9-55.0.0.0.2.ELsmp #1 SMP Wed May 2 14:59:56 PDT 2007 i686 i686 i386 GNU/Linux (8 Replies)
Hi all,
I want to do a very simple thing with sed. I want to print out the line number of a disk I have defined in /etc/exports, so I do:
It's all good, but here's the problem. When I define md0 in a variable, I get nothing from sed:
Why is that? can anybody please help?
Thanks (2 Replies)
Hi all,
I am using HP-UX and I have just noticed that when I log into the network it seems to save the previous windows that were subsequently closed on previous occasions. Does anyone know when I log in, it seems to display these previous windows, e.g. nedit windows open again?
Does... (1 Reply)
Hi all,
I'm having this scenario which for the moment I cannot resolve. :(
I wrote a script to make a dump/export of the oracle database. and then put this entry on crontab to be executed daily for example.
The script is like below:
cat /home/oracle/scripts/db_backup.sh
#!/bin/ksh
... (3 Replies)
Hi all !
I noticed something very weird.
I have a large pipe delimited file (20 fields/3,000 records) that looks like that:
AAA|BBB|11111|22222|...|($NF of record 1)
CCC|DDD|33333|44444|...|($NF of record 2)
CCC|DDD|55555|66666|...|($NF of record 3)
For the lines with same 1st and 2nd... (3 Replies)
Can someone please explain the strange behaviour.. I was just trying a few things to learn awk..
in the below code when I start the braces in the same line, the output is as expected, when I start at next line, output is displayed twice.
Please see the file, code I tried and output below.
... (2 Replies)
Discussion started by: Kulasekar
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)