search: disable phrase searching, for now

There probably needs to be an option to enable this
independently of indexlevel; but for now this is
the safest option.

And, as I discovered during the development of the
indexlevel option, Xapian does a pretty good job of
finding phrases without position data, anyways.

diff --git a/lib/PublicInbox/Search.pm b/lib/PublicInbox/Search.pm
index 090d998b6c2c3d6fda2365d9ae92ada6f0dd40e6..bb4bd454dd9242d51dd886ad3ae57a1c320c3e8e 100644 (file)
--- a/lib/PublicInbox/Search.pm
+++ b/lib/PublicInbox/Search.pm
@@ -45,7 +45,11 @@ use constant {
 
        # n.b. FLAG_PURE_NOT is expensive not suitable for a public website
        # as it could become a denial-of-service vector
-       QP_FLAGS => FLAG_PHRASE|FLAG_BOOLEAN|FLAG_LOVEHATE|FLAG_WILDCARD,
+       #
+       # FLAG_PHRASE also seems to cause performance problems sometimes.
+       # TODO: make this an option, maybe?
+       # or make indexlevel=medium as default
+       QP_FLAGS => FLAG_BOOLEAN|FLAG_LOVEHATE|FLAG_WILDCARD,
 };
 
 my %bool_pfx_external = (