Hello people,
I have a huge file of say 1 gb called A123.txt..
to get the word count, i do
This gives me a count of say 122898.
Now what i do is, i divide this by 4 ie. 122888/4=30722
Now i copy the content as per the above count (30722) and give some name to each of the 4 files, since the size is too huge...
Is there a split function in shell? (not awk)
Coz i got a string as input and needed to split it.
eg. input = "abc:123:def:www"
I need to split it into 4 variable which contains abc,123,def,www.
Is there anyway i can do tat? (1 Reply)
I have gone through all the threads in the forum and tested out different things. I am trying to split a 3GB file into multiple files. Some files are even larger than this.
For example:
split -l 3000000 filename.txt
This is very slow and it splits the file with 3 million records in each... (10 Replies)
I have a file that reads "#ID, First, P1(40), P2(40), P3(40)..." and I need to split this line up.
I first did @scores = split(/,/, $input);
But I need to split it up and get the the parentheses with numbers split up too, in order to add them together later.
I know I need to do at least... (1 Reply)
Hi there,
Can someone tell me why the why the element of output is not the same order as the original data?
Below is the value of column 11 of 2nd line,... (4 Replies)
I'm trying to do a split using two delimiters. The first delimiter is ": " (or we could call it :\s). The second is "\n".
How can or these delimiters so I can toss the values into an array without issue?
I tried @array = split /:\s|\n/, $myvar;
This doesn't seem to be working.
Any an... (3 Replies)
Hello;
I have a file consists of 4 columns separated by tab. The problem is the third fields. Some of the them are very long but can be split by the vertical bar "|". Also some of them do not contain the string "UniProt", but I could ignore it at this moment, and sort the file afterwards. Here is... (5 Replies)
Hi all, I have a strange problem that I have finally given up on and thought id start hitting the forums.. Any help is greatly appreiciated.
I have recently attached two new physical disks to my system and created a new volume group which inlcude these. My aim, is to create a logical volume of... (1 Reply)
Hello,
I need to split a file by number of records and rename each split file with actual filename pre-pended with 3 digit split number.
What I have tried is the below command with 2 digit numeric value
split -l 3 -d abc.txt F (# Will Produce split Files as F00 F01 F02)
How to produce... (19 Replies)
Discussion started by: techedipro
19 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)