Calculating which shard(s) to send $in queries to was taking a long time. This fix changes mongos to stop limiting the shards to send to after the first $in clause - possibly sending the query to more shards than necessary, but saving time. SERVER-4745.

1 files changed, 4 insertions, 5 deletions

diff --git a/db/queryutil.cpp b/db/queryutil.cpp
index ef5ae3a6fdb..47f89ada5bc 100644
--- a/db/queryutil.cpp
+++ b/db/queryutil.cpp
@@ -1021,13 +1021,13 @@ namespace mongo {
         BoundBuilders builders;
         builders.push_back( make_pair( shared_ptr<BSONObjBuilder>( new BSONObjBuilder() ), shared_ptr<BSONObjBuilder>( new BSONObjBuilder() ) ) );
         BSONObjIterator i( keyPattern );
-        bool ineq = false; // until ineq is true, we are just dealing with equality and $in bounds
+        bool equalityOnly = true; // until equalityOnly is false, we are just dealing with equality (no range or $in querys).
         while( i.more() ) {
             BSONElement e = i.next();
             const FieldRange &fr = range( e.fieldName() );
             int number = (int) e.number(); // returns 0.0 if not numeric
             bool forward = ( ( number >= 0 ? 1 : -1 ) * ( direction >= 0 ? 1 : -1 ) > 0 );
-            if ( !ineq ) {
+            if ( equalityOnly ) {
                 if ( fr.equality() ) {
                     for( BoundBuilders::const_iterator j = builders.begin(); j != builders.end(); ++j ) {
                         j->first->appendAs( fr.min(), "" );
@@ -1035,9 +1035,8 @@ namespace mongo {
                     }
                 }
                 else {
-                    if ( !fr.inQuery() ) {
-                        ineq = true;
-                    }
+                    equalityOnly = false;
+
                     BoundBuilders newBuilders;
                     const vector<FieldInterval> &intervals = fr.intervals();
                     for( BoundBuilders::const_iterator i = builders.begin(); i != builders.end(); ++i ) {