implement aggregate_locking design

Now aggregation will not lock the wiki. Any changes made during aggregaton are
merged in with the changed state accumulated while aggregating. A separate
lock file prevents multiple concurrent aggregators. Garbage collection
of orphaned guids is much improved. loadstate() is only called once
per process, so tricky support for reloading wiki state is not needed.

(Tested fairly thuroughly.)
master
Joey Hess 2008-02-03 16:48:26 -05:00
parent 38affb0c1c
commit 9d54cc4659
4 changed files with 172 additions and 104 deletions

View File

@ -33,33 +33,62 @@ sub getopt () { #{{{
sub checkconfig () { #{{{
if ($config{aggregate} && ! ($config{post_commit} &&
IkiWiki::commit_hook_enabled())) {
if (! IkiWiki::lockwiki(0)) {
debug("wiki is locked by another process, not aggregating");
exit 1;
}
# See if any feeds need aggregation.
loadstate();
IkiWiki::loadindex();
aggregate();
expire();
savestate();
clearstate();
my @feeds=needsaggregate();
return unless @feeds;
if (! lockaggregate()) {
debug("an aggregation process is already running");
return;
}
# force a later rebuild of source pages
$IkiWiki::forcerebuild{$_->{sourcepage}}=1
foreach @feeds;
IkiWiki::unlockwiki();
# Fork a child process to handle the aggregation.
# The parent process will then handle building the
# result. This avoids messy code to clear state
# accumulated while aggregating.
defined(my $pid = fork) or error("Can't fork: $!");
if (! $pid) {
IkiWiki::loadindex();
# Aggregation happens without the main wiki lock
# being held. This allows editing pages etc while
# aggregation is running.
aggregate(@feeds);
IkiWiki::lockwiki;
# Merge changes, since aggregation state may have
# changed on disk while the aggregation was happening.
mergestate();
expire();
savestate();
IkiWiki::unlockwiki;
exit 0;
}
waitpid($pid,0);
if ($?) {
error "aggregation failed with code $?";
}
clearstate();
unlockaggregate();
}
} #}}}
sub needsbuild (@) { #{{{
my $needsbuild=shift;
loadstate(); # if not already loaded
loadstate();
foreach my $feed (values %feeds) {
if (exists $pagesources{$feed->{sourcepage}} &&
grep { $_ eq $pagesources{$feed->{sourcepage}} } @$needsbuild) {
# Mark all feeds originating on this page as removable;
# preprocess will unmark those that still exist.
remove_feeds($feed->{sourcepage});
# Mark all feeds originating on this page as
# not yet seen; preprocess will unmark those that
# still exist.
markunseen($feed->{sourcepage});
}
}
} # }}}
@ -92,8 +121,7 @@ sub preprocess (@) { #{{{
$feed->{updateinterval}=defined $params{updateinterval} ? $params{updateinterval} * 60 : 15 * 60;
$feed->{expireage}=defined $params{expireage} ? $params{expireage} : 0;
$feed->{expirecount}=defined $params{expirecount} ? $params{expirecount} : 0;
delete $feed->{remove};
delete $feed->{expired};
delete $feed->{unseen};
$feed->{lastupdate}=0 unless defined $feed->{lastupdate};
$feed->{numposts}=0 unless defined $feed->{numposts};
$feed->{newposts}=0 unless defined $feed->{newposts};
@ -123,16 +151,27 @@ sub delete (@) { #{{{
# Remove feed data for removed pages.
foreach my $file (@files) {
my $page=pagename($file);
remove_feeds($page);
markunseen($page);
}
} #}}}
sub markunseen ($) { #{{{
my $page=shift;
foreach my $id (keys %feeds) {
if ($feeds{$id}->{sourcepage} eq $page) {
$feeds{$id}->{unseen}=1;
}
}
} #}}}
my $state_loaded=0;
sub loadstate () { #{{{
return if $state_loaded;
$state_loaded=1;
if (-e "$config{wikistatedir}/aggregate") {
open(IN, "<", "$config{wikistatedir}/aggregate") ||
open(IN, "$config{wikistatedir}/aggregate") ||
die "$config{wikistatedir}/aggregate: $!";
while (<IN>) {
$_=IkiWiki::possibly_foolish_untaint($_);
@ -166,32 +205,13 @@ sub loadstate () { #{{{
sub savestate () { #{{{
return unless $state_loaded;
garbage_collect();
eval q{use HTML::Entities};
error($@) if $@;
my $newfile="$config{wikistatedir}/aggregate.new";
my $cleanup = sub { unlink($newfile) };
open (OUT, ">", $newfile) || error("open $newfile: $!", $cleanup);
open (OUT, ">$newfile") || error("open $newfile: $!", $cleanup);
foreach my $data (values %feeds, values %guids) {
if ($data->{remove}) {
if ($data->{name}) {
foreach my $guid (values %guids) {
if ($guid->{feed} eq $data->{name}) {
$guid->{remove}=1;
}
}
}
else {
unlink pagefile($data->{page})
if exists $data->{page};
}
next;
}
elsif ($data->{expired} && exists $data->{page}) {
unlink pagefile($data->{page});
delete $data->{page};
delete $data->{md5};
}
my @line;
foreach my $field (keys %$data) {
if ($field eq "name" || $field eq "feed" ||
@ -212,6 +232,63 @@ sub savestate () { #{{{
error("rename $newfile: $!", $cleanup);
} #}}}
sub garbage_collect () { #{{{
foreach my $name (keys %feeds) {
# remove any feeds that were not seen while building the pages
# that used to contain them
if ($feeds{$name}->{unseen}) {
delete $feeds{$name};
}
}
foreach my $guid (values %guids) {
# any guid whose feed is gone should be removed
if (! exists $feeds{$guid->{feed}}) {
unlink pagefile($guid->{page})
if exists $guid->{page};
delete $guids{$guid->{guid}};
}
# handle expired guids
elsif ($guid->{expired} && exists $guid->{page}) {
unlink pagefile($guid->{page});
delete $guid->{page};
delete $guid->{md5};
}
}
} #}}}
sub mergestate () { #{{{
# Load the current state in from disk, and merge into it
# values from the state in memory that might have changed
# during aggregation.
my %myfeeds=%feeds;
my %myguids=%guids;
clearstate();
loadstate();
# All that can change in feed state during aggregation is a few
# fields.
foreach my $name (keys %myfeeds) {
if (exists $feeds{$name}) {
foreach my $field (qw{message lastupdate numposts
newposts error}) {
$feeds{$name}->{$field}=$myfeeds{$name}->{$field};
}
}
}
# New guids can be created during aggregation.
# It's also possible that guids were removed from the on-disk state
# while the aggregation was in process. That would only happen if
# their feed was also removed, so any removed guids added back here
# will be garbage collected later.
foreach my $guid (keys %myguids) {
if (! exists $guids{$guid}) {
$guids{$guid}=$myguids{$guid};
}
}
} #}}}
sub clearstate () { #{{{
%feeds=();
%guids=();
@ -249,7 +326,12 @@ sub expire () { #{{{
}
} #}}}
sub aggregate () { #{{{
sub needsaggregate () { #{{{
return values %feeds if $config{rebuild};
return grep { time - $_->{lastupdate} >= $_->{updateinterval} } values %feeds;
} #}}}
sub aggregate (@) { #{{{
eval q{use XML::Feed};
error($@) if $@;
eval q{use URI::Fetch};
@ -257,15 +339,12 @@ sub aggregate () { #{{{
eval q{use HTML::Entities};
error($@) if $@;
foreach my $feed (values %feeds) {
next unless $config{rebuild} ||
time - $feed->{lastupdate} >= $feed->{updateinterval};
foreach my $feed (@_) {
$feed->{lastupdate}=time;
$feed->{newposts}=0;
$feed->{message}=sprintf(gettext("processed ok at %s"),
displaytime($feed->{lastupdate}));
$feed->{error}=0;
$IkiWiki::forcerebuild{$feed->{sourcepage}}=1;
debug(sprintf(gettext("checking feed %s ..."), $feed->{name}));
@ -473,18 +552,6 @@ sub htmlabs ($$) { #{{{
return $ret;
} #}}}
sub remove_feeds () { #{{{
my $page=shift;
my %removed;
foreach my $id (keys %feeds) {
if ($feeds{$id}->{sourcepage} eq $page) {
$feeds{$id}->{remove}=1;
$removed{$id}=1;
}
}
} #}}}
sub pagefile ($) { #{{{
my $page=shift;

7
debian/changelog vendored
View File

@ -6,19 +6,22 @@ ikiwiki (2.31) UNRELEASED; urgency=low
that contributes to a page's content and using the youngest of them all,
as well as special cases for things like the version plugin, and it's just
too complex to do.
* aggregate: Forking a child broke the one state that mattered: Forcing
the aggregating page to be rebuilt. Fix this.
* cgi hooks are now run before ikiwiki state is loaded.
* This allows locking the wiki before loading state, which avoids some
tricky locking code when saving a web edit.
* poll: This plugin turns out to have edited pages w/o doing any locking.
Oops. Convert it from a cgi to a sessioncgi hook, which will work
much better.
* aggregate: Revert use of forking to not save state, that was not the right
approach.
* recentchanges: Improve handling of links on the very static changes pages
by thunking to the CGI, which can redirect to the page, or allow it to be
created if it doesn't exist.
* recentchanges: Exipre all *._change pages, even if the directory
they're in has changed.
* aggregate: Lots of changes; aggregation can now run without locking the
wiki, and there is a separate aggregatelock to prevent multiple concurrent
aggregation runs.
-- Joey Hess <joeyh@debian.org> Sat, 02 Feb 2008 23:36:31 -0500

View File

@ -46,16 +46,12 @@ would be loaded, and there would be no reason to worry about aggregating.
Or aggregation could be kept in checkconfig, like so:
* lock wiki
* load aggregation state
* unlock wiki
* get list of feeds needing aggregation
* exit if none
* attempt to take aggregation lock, exit if another aggregation is happening
* fork a child process to do the aggregation
* lock wiki
* load wiki state (needed for aggregation to run)
* unlock wiki
* aggregate
* lock wiki
* reload aggregation state
@ -64,3 +60,5 @@ Or aggregation could be kept in checkconfig, like so:
* drop aggregation lock
* force rebuild of sourcepages of feeds that were aggregated
* exit checkconfig and continue with usual refresh process
[[done]]

View File

@ -8,7 +8,7 @@ msgid ""
msgstr ""
"Project-Id-Version: PACKAGE VERSION\n"
"Report-Msgid-Bugs-To: \n"
"POT-Creation-Date: 2008-02-03 14:52-0500\n"
"POT-Creation-Date: 2008-02-03 16:05-0500\n"
"PO-Revision-Date: YEAR-MO-DA HO:MI+ZONE\n"
"Last-Translator: FULL NAME <EMAIL@ADDRESS>\n"
"Language-Team: LANGUAGE <LL@li.org>\n"
@ -67,67 +67,67 @@ msgstr ""
msgid "You are banned."
msgstr ""
#: ../IkiWiki/Plugin/aggregate.pm:72
#: ../IkiWiki/Plugin/aggregate.pm:100
#, perl-format
msgid "missing %s parameter"
msgstr ""
#: ../IkiWiki/Plugin/aggregate.pm:100
#: ../IkiWiki/Plugin/aggregate.pm:127
msgid "new feed"
msgstr ""
#: ../IkiWiki/Plugin/aggregate.pm:114
#: ../IkiWiki/Plugin/aggregate.pm:141
msgid "posts"
msgstr ""
#: ../IkiWiki/Plugin/aggregate.pm:116
#: ../IkiWiki/Plugin/aggregate.pm:143
msgid "new"
msgstr ""
#: ../IkiWiki/Plugin/aggregate.pm:232
#, perl-format
msgid "expiring %s (%s days old)"
msgstr ""
#: ../IkiWiki/Plugin/aggregate.pm:239
#, perl-format
msgid "expiring %s"
msgstr ""
#: ../IkiWiki/Plugin/aggregate.pm:265
#, perl-format
msgid "processed ok at %s"
msgstr ""
#: ../IkiWiki/Plugin/aggregate.pm:270
#, perl-format
msgid "checking feed %s ..."
msgstr ""
#: ../IkiWiki/Plugin/aggregate.pm:275
#, perl-format
msgid "could not find feed at %s"
msgstr ""
#: ../IkiWiki/Plugin/aggregate.pm:290
msgid "feed not found"
msgstr ""
#: ../IkiWiki/Plugin/aggregate.pm:301
#, perl-format
msgid "(invalid UTF-8 stripped from feed)"
msgstr ""
#: ../IkiWiki/Plugin/aggregate.pm:307
#, perl-format
msgid "expiring %s (%s days old)"
msgstr ""
#: ../IkiWiki/Plugin/aggregate.pm:314
#, perl-format
msgid "expiring %s"
msgstr ""
#: ../IkiWiki/Plugin/aggregate.pm:343
#, perl-format
msgid "processed ok at %s"
msgstr ""
#: ../IkiWiki/Plugin/aggregate.pm:347
#, perl-format
msgid "checking feed %s ..."
msgstr ""
#: ../IkiWiki/Plugin/aggregate.pm:352
#, perl-format
msgid "could not find feed at %s"
msgstr ""
#: ../IkiWiki/Plugin/aggregate.pm:367
msgid "feed not found"
msgstr ""
#: ../IkiWiki/Plugin/aggregate.pm:378
#, perl-format
msgid "(invalid UTF-8 stripped from feed)"
msgstr ""
#: ../IkiWiki/Plugin/aggregate.pm:384
#, perl-format
msgid "(feed entities escaped)"
msgstr ""
#: ../IkiWiki/Plugin/aggregate.pm:313
#: ../IkiWiki/Plugin/aggregate.pm:390
msgid "feed crashed XML::Feed!"
msgstr ""
#: ../IkiWiki/Plugin/aggregate.pm:387
#: ../IkiWiki/Plugin/aggregate.pm:464
#, perl-format
msgid "creating new page %s"
msgstr ""