[PATCH] view: stop storing all MIME objects on large threads

[Eric Wong <e@80x24.org>]

While we try to discard the $smsg (SearchMsg) objects quickly,
they remain referenced via $node (SearchThread::Msg) objects,
which are stored forever in $ctx->{mapping} to cull redundant
words out of subjects in the thread skeleton.

This significantly cuts memory bloat with large search results
with '&x=t'.  Now, the search results overhead of
SearchThread::Msg and linked objects are stable at around 350K
instead of ~7M per response in a rough test (there's more
savings to be had in the same areas).

Several hundred kilobytes is still huge and a large per-client
cost; but it's far better than MEGABYTES per-client.
---
 lib/PublicInbox/View.pm | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/lib/PublicInbox/View.pm b/lib/PublicInbox/View.pm
index bb49c03..416cb4a 100644
--- a/lib/PublicInbox/View.pm
+++ b/lib/PublicInbox/View.pm
@@ -218,7 +218,7 @@ sub index_entry {
 	$rv .= $subj . "\n";
 	$rv .= _th_index_lite($mid_raw, \$irt, $id, $ctx);
 	my @tocc;
-	my $mime = $smsg->{mime};
+	my $mime = delete $smsg->{mime}; # critical to memory use
 	my $hdr = $mime->header_obj;
 	my $from = _hdr_names_html($hdr, 'From');
 	obfuscate_addrs($obfs_ibx, $from) if $obfs_ibx;
-- 
EW