I have a query in relation to a couple of machines I have set up. We will call them machine SUN and HPUX and they are running those operating systems respectively. The SUN machine is acting as an NIS server and the HPUX machine as an NIS client. Now the HPUX machine also has a an auto mounted file... (11 Replies)
I have an RPM that I am trying to install and it keeps coming back with:
I know I could kill the bird by throwing a "yum install *perl*" at it, but this seems like hurling a skyscraper at an ant...
any better suggestions? (2 Replies)
A fresh installation was done in a machine of name arenal1 on Feb 26. But in the /var/adm/messages of the machine, there are messages having date Nov 12. Also the name of the machine is also different in the messages. Can anyone please tell me the reason for this discrepancy. (15 Replies)
During a file-system cleanup I noticed a strange behavior of awk (HP-UX 11iv3 / IA64). When summing up the size of files in one directory it gives different numbers when using print as opposed to printf:
find . -type f -name '*.dmp.Z' -mtime +35 -exec ls -l {} \+ | \
awk 'BEGIN{ OFMT="%f" } {... (1 Reply)
When I run 'top' command,I see the following
Memory: 32G real, 12G free, 96G swap free
Though it shows as 12G free,I am not able to account for processes that consume the rest 20G.
In my understanding some process should be consuming atleast 15-16 G but I am not able to find them.
Is... (1 Reply)
Hi all,
We are seeing an odd problem on one of our new servers. It seems to be reporting 4MB less RAM than is installed:
# prtconf | grep Mem
Memory size: 32764 Megabytes
Our other servers for example shows none missing:
# prtconf | grep Mem
Memory size: 32768 Megabytes
Both... (5 Replies)
> reverse=`tput rev`
> revert=`tput sgr0`
> var="This is some note."
> echo $var
This is some note.
> var2="This is ${reverse}some${revert} note."
> echo $var2
This is some note.
> var3=$(echo $var | sed 's/some/${reverse}some${revert}/g')
> echo $var3
This is... (3 Replies)
Hi All,
I have around 900 Select Sql's which I would like to run in an awk script and print the output of those sql's in an txt file.
Can you anyone pls let me know how do I do it and execute the awk script? Thanks. (4 Replies)
Hey there! I'm a new user here who registered because I couldn't get these kind of questions answered in the place I directly com from. :o
I've found a discrepancy in total RAM used and I can't figure out why it is. My only guess is there are some RAM used by some stuff impossible to identify,... (2 Replies)
#include<stdio.h>
#include<stdlib.h>
#include<sys/time.h>
#include<time.h>
#include "rdtsc.h"
#define SIZE 4*64*1024
int main()
{
unsigned long long a,b;
int arr={0};
int i;
register int r;
a=rdtsc();
r=arr;
b=rdtsc();
printf("1st element Access Cycles = %llu\n",b-a); (2 Replies)
Discussion started by: Vaibhavs1985
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)