ambiser
/
btrbk
mirror of https://github.com/digint/btrbk
9
0
Fork 0
Code Issues Packages Projects Releases Wiki Activity

btrbk: added "snapshot_create onchange", which skips snapshot creation if the latest snapshot is up-to-date (i.e. has same generation as the source subvolume)

pull/30/head
Axel Burri 2015-05-25 14:38:32 +02:00
parent 27e150878c
commit 16355b848d
3 changed files with 58 additions and 16 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

6
ChangeLog
View File

@ -1,3 +1,9 @@
btrbk-current
* Added "snapshot_create onchange", which skips snapshot creation if
the latest snapshot is up-to-date (i.e. has same generation as the
source subvolume)
btrbk-0.18.0
* MIGRATION

47
btrbk
View File

@ -47,7 +47,7 @@ use Date::Calc qw(Today Delta_Days Day_of_Week);
use Getopt::Std;
use Data::Dumper;
our $VERSION = "0.18.0";
our $VERSION = "0.19.0-dev";
our $AUTHOR = 'Axel Burri <axel@tty0.ch>';
our $PROJECT_HOME = '<http://www.digint.ch/btrbk/>';
@ -62,7 +62,7 @@ my %config_options = (
# NOTE: keys "volume", "subvolume" and "target" are hardcoded
snapshot_dir => { default => undef, accept_file => { relative => 1 } },
snapshot_name => { default => undef, accept_file => { name_only => 1 }, context => [ "subvolume" ] },
snapshot_create => { default => "always", accept => [ "no", "always", "ondemand" ] },
snapshot_create => { default => "always", accept => [ "no", "always", "ondemand", "onchange" ] },
incremental => { default => "yes", accept => [ "yes", "no", "strict" ] },
resume_missing => { default => "yes", accept => [ "yes", "no" ] },
preserve_day_of_week => { default => "sunday", accept => [ (keys %day_of_week_map) ] },
@ -1173,6 +1173,27 @@ sub get_latest_common($$$;$)
}
sub get_latest_snapshot_child($$)
{
my $sroot = shift || die;
my $svol = shift // die;
my $latest = undef;
my $gen = -1;
foreach (get_snapshot_children($sroot, $svol)) {
if($_->{gen} > $gen) {
$latest = $_;
$gen = $_->{gen};
}
}
if($latest) {
DEBUG "Latest snapshot child for \"$svol->{PRINT}#$svol->{gen}\" is: $latest->{PRINT}#$latest->{gen}";
} else {
DEBUG "No latest snapshots found for: $svol->{PRINT}";
}
return $latest;
}
sub _origin_tree
{
my $prefix = shift;
@ -1782,13 +1803,23 @@ MAIN:
my $snapshot_basename = config_key($config_subvol, "snapshot_name") // die;
# check if we need to create a snapshot
my $snapshot_create = config_key($config_subvol, "snapshot_create") // "no";
if($snapshot_create eq "no") {
DEBUG "Snapshot creation disabled: snapshot_create=no";
my $snapshot_create = config_key($config_subvol, "snapshot_create");
if(not $snapshot_create) {
DEBUG "Snapshot creation disabled (snapshot_create=no)";
next;
}
if($snapshot_create eq "always") {
DEBUG "Snapshot creation enabled: snapshot_create=always";
elsif($snapshot_create eq "always") {
DEBUG "Snapshot creation enabled (snapshot_create=always)";
}
elsif($snapshot_create eq "onchange") {
# check if latest snapshot is up-to-date with source subvolume (by generation)
my $latest = get_latest_snapshot_child($sroot, $svol);
if($latest && ($latest->{gen} == $svol->{gen})) {
INFO "Snapshot creation skipped: snapshot_create=onchange, snapshot is up-to-date: $latest->{PRINT}";
$config_subvol->{SNAPSHOT_UP_TO_DATE} = $latest;
next;
}
DEBUG "Snapshot creation enabled: snapshot_create=onchange, gen=$svol->{gen} > snapshot_gen=$latest->{gen}";
}
elsif($snapshot_create eq "ondemand") {
my $snapshot_needed = 0;
@ -2106,6 +2137,7 @@ MAIN:
push @subvol_out, "!!! Subvolume \"$svol->{PRINT}\" aborted: $config_subvol->{ABORTED}";
$err_count++ unless($config_subvol->{ABORTED_NOERR});
}
push @subvol_out, "=== $config_subvol->{SNAPSHOT_UP_TO_DATE}->{PRINT}" if($config_subvol->{SNAPSHOT_UP_TO_DATE});
push @subvol_out, "+++ $config_subvol->{SNAPSHOT}->{PRINT}" if($config_subvol->{SNAPSHOT});
if($config_subvol->{SUBVOL_DELETED}) {
push @subvol_out, "--- $_->{PRINT}" foreach(sort { $a->{PATH} cmp $b->{PATH} } @{$config_subvol->{SUBVOL_DELETED}});
@ -2146,6 +2178,7 @@ MAIN:
print " Date: " . localtime($start_time) . "\n";
print " Config: $config->{SRC_FILE}\n";
print "\nLegend:\n";
print " === up-to-date subvolume (source snapshot)\n";
print " +++ created subvolume (source snapshot)\n";
print " --- deleted subvolume\n";
print " *** received subvolume (non-incremental)\n";

21
doc/btrbk.conf.5
View File

@ -55,15 +55,18 @@ will fail if it is not present.
backup). This option is only valid in the \fItarget\fR
section. Defaults to \fI<subvolume-name>\fR.
.TP
\fBsnapshot_create\fR always|ondemand|no
If set to \[lq]ondemand\[rq], the snapshots are only created if the
target subvolume is reachable (useful if you are tight on disk space
and you only need btrbk for backups to an external disk which is not
always connected). If set to \[lq]always\[rq], the snapshots are
always created, regardless of the target reachability. If set to
\[lq]no\[rq], the snapshots are never created (useful in conjunction
with the \fIresume_missing\fR option if another instance of btrbk is
taking care of snapshot creation). Defaults to \[lq]always\[rq].
\fBsnapshot_create\fR always|ondemand|onchange|no
If set to \[lq]ondemand\[rq], snapshots are only created if the target
subvolume is reachable (useful if you are tight on disk space and you
only need btrbk for backups to an external disk which is not always
connected). If set to \[lq]onchange\[rq], snapshots are only created
if the source subvolume has changed since the last snapshot (more
precisely: if the btrfs generation has been increased since the last
snapshot). If set to \[lq]always\[rq], snapshots are always
created. If set to \[lq]no\[rq], the snapshots are never created
(useful in conjunction with the \fIresume_missing\fR option if another
instance of btrbk is taking care of snapshot creation). Defaults to
\[lq]always\[rq].
.TP
\fBincremental\fR yes|no|strict
If set, incremental backups are created. If set to \[lq]strict\[rq],