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, 1 insertions, 1 deletions

diff --git a/lib/PublicInbox/Mbox.pm b/lib/PublicInbox/Mbox.pm
index cfe34d9c..2ef8ff2b 100644
--- a/lib/PublicInbox/Mbox.pm
+++ b/lib/PublicInbox/Mbox.pm
@@ -20,7 +20,7 @@ sub getline {
         my $ibx = $ctx->{ibx};
         my $eml = delete($ctx->{eml}) // $ibx->smsg_eml($smsg) // return;
         my $n = $ctx->{smsg} = $ibx->over->next_by_mid(@{$ctx->{next_arg}});
-        $ctx->zadd(msg_hdr($ctx, $eml));
+        $ctx->zmore(msg_hdr($ctx, $eml));
         if ($n) {
                 $ctx->translate(msg_body($eml));
         } else { # last message