cyteen
/
sanoid
mirror of https://github.com/jimsalterjrs/sanoid
1
0
Fork 0
Code Issues Packages Projects Releases Wiki Activity

write cache files in an atomic way to prevent race conditions

This commit is contained in:
Christoph Klaffl 2024-04-24 00:09:40 +02:00
parent 6f74c7c4b3
commit 9c0468ee45
No known key found for this signature in database
GPG Key ID: 8FC1D76EED4970D2
1 changed files with 6 additions and 3 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

9
sanoid
View File

@ -868,9 +868,10 @@ sub getsnaps {
@rawsnaps = <FH>; @rawsnaps = <FH>;
close FH; close FH;
open FH, "> $cache" or die 'Could not write to $cache!\n'; open FH, "> $cache.tmp" or die 'Could not write to $cache.tmp!\n';
print FH @rawsnaps; print FH @rawsnaps;
close FH; close FH;
rename("$cache.tmp", "$cache") or die 'Could not rename to $cache!\n';
removelock('sanoid_cacheupdate'); removelock('sanoid_cacheupdate');
} else { } else {
if ($args{'verbose'}) { print "INFO: deferring cache update - valid cache update lock held by another sanoid process.\n"; } if ($args{'verbose'}) { print "INFO: deferring cache update - valid cache update lock held by another sanoid process.\n"; }
@ -1105,9 +1106,10 @@ sub init {
print "INFO: dataset cache expired - updating from zfs list.\n"; print "INFO: dataset cache expired - updating from zfs list.\n";
} }
} }
open FH, "> $cachedatasetspath" or die 'Could not write to $cachedatasetspath!\n'; open FH, "> $cachedatasetspath.tmp" or die 'Could not write to $cachedatasetspath.tmp!\n';
print FH @updatedatasets; print FH @updatedatasets;
close FH; close FH;
rename("$cachedatasetspath.tmp", "$cachedatasetspath") or die 'Could not rename to $cachedatasetspath!\n';
removelock('sanoid_cachedatasetupdate'); removelock('sanoid_cachedatasetupdate');
} else { } else {
if ($args{'verbose'}) { print "INFO: deferring dataset cache update - valid cache update lock held by another sanoid process.\n"; } if ($args{'verbose'}) { print "INFO: deferring dataset cache update - valid cache update lock held by another sanoid process.\n"; }
@ -1731,13 +1733,14 @@ sub removecachedsnapshots {
my @rawsnaps = <FH>; my @rawsnaps = <FH>;
close FH; close FH;
open FH, "> $cache" or die 'Could not write to $cache!\n'; open FH, "> $cache.tmp" or die 'Could not write to $cache.tmp!\n';
foreach my $snapline ( @rawsnaps ) { foreach my $snapline ( @rawsnaps ) {
my @columns = split("\t", $snapline); my @columns = split("\t", $snapline);
my $snap = $columns[0]; my $snap = $columns[0];
print FH $snapline unless ( exists($pruned{$snap}) ); print FH $snapline unless ( exists($pruned{$snap}) );
} }
close FH; close FH;
rename("$cache.tmp", "$cache") or die 'Could not rename to $cache!\n';
removelock('sanoid_cacheupdate'); removelock('sanoid_cacheupdate');
%snaps = getsnaps(\%config,$cacheTTL,0); %snaps = getsnaps(\%config,$cacheTTL,0);