www: use PerlIO::scalar (zfh) for buffering

Calling Compress::Raw::Zlib::deflate is fairly expensive.
Relying on the `.=' (concat) operator inside ->zadd operator is
faster, but the method dispatch overhead is noticeable compared
to the original code where we had bare `.=' littered throughout.

Fortunately, `print' and `say' with the PerlIO::scalar IO layer
appears to offer better performance without high method dispatch
overhead.  This doesn't allow us to save as much memory as I
originally hoped, but does allow us to rely less on concat
operators in other places and just pass a list of args to
`print' and `say' as a appropriate.

This does reduce scratchpad use, however, allowing for large
memory savings, and we still ->deflate every single $eml.

1 files changed, 2 insertions, 2 deletions

diff --git a/lib/PublicInbox/SearchView.pm b/lib/PublicInbox/SearchView.pm
index b18947ee..8932c73d 100644
--- a/lib/PublicInbox/SearchView.pm
+++ b/lib/PublicInbox/SearchView.pm
@@ -331,10 +331,10 @@ sub mset_thread {
 # callback for PublicInbox::WwwStream::getline
 sub mset_thread_i {
         my ($ctx, $eml) = @_;
-        $ctx->zadd($ctx->html_top) if exists $ctx->{-html_tip};
+        print { $ctx->zfh } $ctx->html_top if exists $ctx->{-html_tip};
         $eml and return PublicInbox::View::eml_entry($ctx, $eml);
         my $smsg = shift @{$ctx->{msgs}} or
-                $ctx->zmore(${delete($ctx->{skel})});
+                print { $ctx->zfh } ${delete($ctx->{skel})};
         $smsg;
 }