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Date: Sun, 10 May 2009 04:45:00 -0000
Subject: [Bug libstdc++/40088]  New: Creating a std::ostringstream object locks a global mutex
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From: "davewx7 at gmail dot com" <gcc-bugzilla@gcc.gnu.org>
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When a std::ostringstream object is created, it references a locale object
which is synchronized by a global mutex.

This causes a significant performance problem for multi-threaded applications
running on systems with many CPU's if they use string streams frequently.


-- 
           Summary: Creating a std::ostringstream object locks a global
                    mutex
           Product: gcc
           Version: 4.3.3
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: libstdc++
        AssignedTo: unassigned at gcc dot gnu dot org
        ReportedBy: davewx7 at gmail dot com


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=40088