package duplication present in (e.g.) a profile. It shows the
number of instances of each package in a closure, along with the
size in bytes of each instance as well as the "waste" (the
difference between the sum of the sizes of all instances and the
average size).
$ ./show-duplication.pl /nix/var/nix/profiles/default
gcc 11
3.3.6 19293318
3.4.4 21425257
...
average 14942970, waste 149429707
coreutils 6
...
average package duplication 1.87628865979381, total size 3486330471, total waste 1335324237, 38.3017114443825% wasted
This utility is useful for measuring the cost in terms of disk space
of the Nix approach.
old generations of *all* profiles in /nix/var/nix/profiles, then
runs the garbage collector. Quick way to get rid of all old stuff.
Of course, one cannot roll back to earlier points in time after
this.
such as open files, current directories, mmaped files, etc. This is
inherently unportable, but it's easy to adapt this script to other
platforms. Currently we call `lsof' and try to read various bits in
/proc/NNN.
The goal is to prevent the garbage collector from removing store
paths that are no longer reachable from a permanent root but that
are still in use (for instance, after the user has done "nix-env -e"
on a running program).
target no longer applies to any available release. This is a
partial fix for NIX-34 (when producing linear patch sequences
between releases, the number of patches grows without bound).
useful way to transfer the closure of a store path to another
machine.
These commands provide functionality previously possible through
`nix-push --copy'. However, they are much more convenient in many
situations (though possibly less efficient).
Example:
$ nix-pack-closure /nix/store/hj232g1r...-subversion-1.3.0 > svn.closure
(on another machine:)
$ nix-unpack-closure < svn.closure
Note that Subversion is added to the store, but not installed into a
user environment. One should do `nix-env -i
/nix/store/hj232g1r...-subversion-1.3.0' for that.
Another example: copy the application Azureus to the machine
`scratchy' through ssh:
$ nix-pack-closure $(which azureus) | ssh scratchy nix-unpack-closure
nix-store query options `--referer' and `--referer-closure' have
been changed to `--referrer' and `--referrer-closure' (but the old
ones are still accepted for compatibility).
the parent runs before the child, it closes some pipe file
descriptors which causes the child to fail due to a bad file
descriptor. So we just use the normal open() function instead.
This fixes NIX-14 (intermittent nix-pull failures).
handle it. It crashed on the 234 MB tetex archive. Probably we
will never be able to handle archives of that size on 32-bit
machines (because bsdiff does everything in memory requiring
max(17*n,9*n+m)+O(1) bytes, so the address space simply isn't
there).