10 More Discussions You Might Find Interesting
1. Shell Programming and Scripting
Hello Experts,
I need to write a shell script to check if a file is open and something is being written to it. I want to know how OS handles it. I checked with lsof command but it is not working. For a test I did this.
while true; do echo `date` >>abc.txt; done
then I checked
lsof |... (5 Replies)
Discussion started by: shekhar_4_u
5 Replies
2. Programming
Hi there,
I have a script running on some DNS servers to calculate TPS, Success Rate and other Performance Counters.
My challenge is to get a Linux Data Visualization Software to collect these performance logs and produce a visualization that will be appealing to Business peeps. A sample of... (2 Replies)
Discussion started by: infinitydon
2 Replies
3. Debian
Hi,
Yesterday I installed and configured logrotate on my Debian machine. I was expecting this to run at 06:25 in the morning and it actually did. All my old logs were compressed and zipped but the new logs were all with size equal to 0 bytes. Processes, while still running ok, they were not... (2 Replies)
Discussion started by: pmatsinopoulos
2 Replies
4. UNIX for Dummies Questions & Answers
We use SAP application cluster on AIX. Communication between 2 of its instances is failing randomly with the following error:
java.net.SocketException: There is no process to read data written to a pipe.
The above error causes a cluster restart if an important communication fails.
Can... (0 Replies)
Discussion started by: RoshniMehta
0 Replies
5. AIX
Hi Everyone,
The machine I'm working on is an AIX 5.3 LPAR running on a P650. oslevel -r shows 5300-08. I'm trying to take a backup to a SCSI tape drive, which has been working up until this point. I know of nothing that has changed recently to cause this problem. But when I try to take a... (0 Replies)
Discussion started by: need2bageek
0 Replies
6. Shell Programming and Scripting
I need to extract data from logs for a mentioned date range..Its quite urgent can anyone help me out with it..its to be written in unix..just thought its better to specify.. (4 Replies)
Discussion started by: sankasu
4 Replies
7. UNIX for Advanced & Expert Users
I have the following code which works on AIX 4.3 but fails at times on AIX 5.3
with:
cat: 0652-054 cannot write to output. There is no process to read data written to a pipe.
validator="${validator_exe} ${validator_parms}"
cmd_line="${CAT} ${data_file} | ${validator}... (6 Replies)
Discussion started by: vigsgb
6 Replies
8. Shell Programming and Scripting
Hi all,
I have a large log file that gets created daily.
I need to be able to pull text out of the log when I hit a pattern including the 7 lines above it and the 3 lines below and output it to a new text file.
Line 1
Line 2
Line 3
Line 4
Line 5
Line 6
Line 7
Pattern
Line 9
Line 10... (11 Replies)
Discussion started by: bas
11 Replies
9. Linux
I'm using growisofs to write DVD, e.g.
$ growisofs -Z /dev/dvd -V "Personal Data, `date +"%b, %d %Y"`" -R -J /mnt/d/*
How can I test whether data was written correctly? md5sum or so? (0 Replies)
Discussion started by: Hitori
0 Replies
10. UNIX for Dummies Questions & Answers
Hi All,
I was able to solve my previous problem (link directory)... but now i have this following problem.
I have mounted a disk from other machine using "mount -F nfs" command. When i run a batch which generates some files in that drive.... after a certain number of files i get... (1 Reply)
Discussion started by: nileshkarania
1 Replies
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)