Hey Neo - or other Unix.com staffers - I've selected my Timezone for the forums - however it's wrong for my Country - as we have Daylight Savings for 6 months of the year - so currently were 1 hour ahead of the time that is provided in the personal options pages. Can we add another for this - no... (5 Replies)
I was trying to schedule a job to run on the last Sunday of October. To stop a process that I have running before daylight savings automatically falls back at 2AM then restart it after the hour has been regained. I thought I was smart (my mistake) and scheduled the 2 entries in cron. I figured that... (3 Replies)
I have a solaris 8 server - and I need to ensure the daylight savings change properly but I dont think its set up correctly:
/usr/sbin/zdump -v -c 2005 $TZ
GB-EIRE Wed Oct 26 12:20:02 2005 UTC = Wed Oct 26 12:20:02 2005 GB isdst=0
GB-EIRE Fri Dec 13 20:45:52 1901 UTC = Fri Dec 13 20:45:52... (5 Replies)
Hello,
I've been looking at coming up with a time change on my Sun workstations since daylight savings time comes early this year. Someone at work told me that a sun patch is available if you have a maintenance contract. It was recommended to just set your systems to GMT time zone. How is this... (5 Replies)
I am running a SUN E450 on solaris (5.7). I have applied the DST patch and the system time is correct. However when users login the get the time wrong (+4 hours) (I am in EDT Zone). Does anyone know where a system wide variable for this could be set. (Root user gets the right time)
Frank (3 Replies)
Our aix unix box did not recognize daylight savings time since it was moved up. Could someone please give me the syntax to change the hour? I looked in man and couldn't find anything, or I missed it. I'm in 3rd grade so if you can, please provide specific instructions.
Thanks! (2 Replies)
Hello everyone
The last sunday I have to check that my servers has change Daylight savings time but only two servers do it and all the rest doesnt.
In smitty where I need to change, for my server take automatic the daylight savings time.
Thanks for your tips
The next its a message for... (0 Replies)
Discussion started by: lo-lp-kl
0 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)