[rhmessaging-commits] rhmessaging commits: r4489 - store/trunk/cpp/lib.

Author: kpvdr Date: 2012-01-04 14:28:32 -0500 (Wed, 04 Jan 2012) New Revision: 4489 Modified: store/trunk/cpp/lib/JournalImpl.cpp store/trunk/cpp/lib/JournalImpl.h Log: BZ 769828: Added a high-level lock on the JournalImpl::loadMessage() method, also reworked the logic of the read invalidation. Tests show that this works correctly under multi-threaded conditions, but is VERY SLOW. This was not designed with multiple read contexts in mind, so there is a lot of thrashing and re-reading, but this should be thread-safe now. Ultimately the flow-to-disk facility which uses this "feature" needs a re-design. Modified: store/trunk/cpp/lib/JournalImpl.cpp =================================================================== --- store/trunk/cpp/lib/JournalImpl.cpp 2012-01-04 17:00:47 UTC (rev 4488) +++ store/trunk/cpp/lib/JournalImpl.cpp 2012-01-04 19:28:32 UTC (rev 4489) @@ -257,6 +257,7 @@ bool JournalImpl::loadMsgContent(u_int64_t rid, std::string& data, size_t length, size_t offset) { + qpid::sys::Mutex::ScopedLock sl(_read_lock); if (_dtok.rid() != rid) { // Free any previous msg @@ -274,8 +275,11 @@ // jumpover points and allow the read to jump back to the first known jumpover point - but this needs // a mechanism in rrfc to accomplish it. Also helpful is a struct containing a journal address - a // combination of lid/offset. - if (oooFlag || rid < lastReadRid) + // NOTE: The second part of the if stmt (rid < lastReadRid) is required to handle browsing. + if (oooFlag || rid < lastReadRid) { _rmgr.invalidate(); + oooRidList.clear(); + } _dlen = 0; _dtok.reset(); _dtok.set_wstate(DataTokenImpl::ENQ); @@ -285,7 +289,6 @@ bool transient = false; bool done = false; bool rid_found = false; - oooRidList.clear(); while (!done) { iores res = read_data_record(&_datap, _dlen, &_xidp, xlen, transient, _external, &_dtok); switch (res) { Modified: store/trunk/cpp/lib/JournalImpl.h =================================================================== --- store/trunk/cpp/lib/JournalImpl.h 2012-01-04 17:00:47 UTC (rev 4488) +++ store/trunk/cpp/lib/JournalImpl.h 2012-01-04 19:28:32 UTC (rev 4489) @@ -83,6 +83,7 @@ bool getEventsTimerSetFlag; boost::intrusive_ptr<qpid::sys::TimerTask> getEventsFireEventsPtr; qpid::sys::Mutex _getf_lock; + qpid::sys::Mutex _read_lock; u_int64_t lastReadRid; // rid of last read msg for loadMsgContent() - detects out-of-order read requests std::vector<u_int64_t> oooRidList; // list of out-of-order rids (greater than current rid) encountered during read sequence