I solicited this site earlier this week and got a good answer for a perl
Script so I made this script from what understood from the answers
But now I have a bug and I'm stump. It doesn't parse correctly the
Output it stays on the first line My $f2 and reprints in a endless loop
I'm sure there... (3 Replies)
Hi All,
Can you please help me interpret the following command. Which I am not able to understand. Also can you please illustrate what it is used for.
perl -pi -e 's/\015//g' text_file.dat
Regards (3 Replies)
Hi guys,
Here is the code:
my @allwords = ();
my %seen=();
foreach my $curr (@allwords) {
$seen{$curr} = 1;
}
@allwords = keys %seen;
my question is: what will @allwords now contain, or how would the entries in the @allwords array be different after this manipulation?
Thank... (3 Replies)
can someone help me how to interpret this line?
my ($class, $hashref) = @_;
my $portfolio = {};
if ($hashref->{portfolio_id}) {
($portfolio) = GEmySQL->get ("select * from portfolio where portfolio.id=$hashref->{portfolio_id}");
}
===============
Question: how do... (2 Replies)
Well, I found myself trying to fix some Perl code (Ive never done any Perl in my life) and I pinpointed the place where the bug could be. But to be sure I have to know what does a few line of code mean:
$files_lim =~ (/^\d*$/)
$files_lim =~ (/^\d*h$/)$files_age =~ s/h//The code where this was... (0 Replies)
Well, I found myself trying to fix some Perl code (Ive never done any Perl in my life) and I pinpointed the place where the bug could be. But to be sure I have to know what does a few line of code mean:
$files_lim =~ (/^\d*$/)
$files_lim =~ (/^\d*h$/)
$files_age =~ s/h//
The code where... (2 Replies)
What is the difference between the two statements below?
A:
$a->{"$fruit"}->{"$color"}->{size} = $size
B:
$size = $a->{"$fruit"}->{"$color"}->{size}
Please assist. Thanks! (0 Replies)
Hi all,
I am trying to build threads which will go to localhost and list the files in given folder.
#!/usr/bin/perl
use threads;
my $t1 = threads->new(\&sub1, 1);
my $t2 = threads->new(\&sub2, 2);
push(@threads,$t1);
push(@threads,$t2);
foreach... (5 Replies)
Hello,
I have many folders under which there is always a file with the same name, which contains the data I need to process later. A perl oneliner was borrowed
perl -e 'print "gene_id\t", join("\t", map {/(.*)\//; $1} @ARGV),"\n";' *_test.trim/level.csvto make a header so that each column... (5 Replies)
Hello,
A former sys admin placed this script on one of our boxes and it needs to be adjusted, but I'm not familiar with perl. Can someone help break this down for me? I'm particularly interested in the -mtime function. What's the time frame being referenced here.
... (5 Replies)
Discussion started by: bbbngowc
5 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)