Uploaded image for project: 'MariaDB MaxScale'
  1. MariaDB MaxScale
  2. MXS-4289

Transaction starts on wrong server with autocommit=0

    XMLWordPrintable

    Details

    • Sprint:
      MXS-SPRINT-166

      Description

      If a transaction is started by a session command that ends up failing while autocommit is disabled, it is possible that the transaction ends up starting on the slave server. In debug builds the debug assertion mentioned later on would be hit. In release builds the session command could end up being executed twice before the transaction would be migrated to the correct server. This could result in a possible transaction replay failure if for some reason the result of the session command isn't idempotent. In practice this should manifest as a temporary slowdown and an unusually long replay failure.


      The mxs3924_sescmd_retry test failed with a debug assertion in route_session_write:

      debug assert at /home/timofey_turenko_mariadb_com/MaxScale/server/modules/routing/readwritesplit/rwsplit_route_stmt.cc:617 failed: Trx target is server4 when m_sescmd_replier is server1 while trx is open (!trx_is_open() || m_trx.target() == m_sescmd_replier)
      alert  : MaxScale 22.08.2 received fatal signal 6. Commit ID: 2c23e5b843d03745ac4ce6a282fe0c837a569a53 System name: Linux Release string: Red Hat Enterprise Linux Server release 7.9 (Maipo)
       
       
      2022-09-12 10:13:41   alert  : (4) MaxScale 22.08.2 received fatal signal 6. Commit ID: 2c23e5b843d03745ac4ce6a282fe0c837a569a53 System name: Linux Release string: Red Hat Enterprise Linux Server release 7.9 (Maipo)
      2022-09-12 10:13:41   alert  : (4) Statement currently being classified: none/unknown
      2022-09-12 10:13:41   alert  : (4) DCB: 0x7f5038019770 Session: 4 Service: RW-Split-Router
      2022-09-12 10:13:41   notice : (4) For a more detailed stacktrace, install GDB and add 'debug=gdb-stacktrace' under the [maxscale] section.
        /lib64/libpthread.so.0(raise+0x2b): ??:?
        /usr/lib64/maxscale/libreadwritesplit.so(_ZN14RWSplitSession19route_session_writeEP5GWBUFhj+0xad8): server/modules/routing/readwritesplit/rwsplit_route_stmt.cc:617 (discriminator 18)
        /usr/lib64/maxscale/libreadwritesplit.so(_ZN14RWSplitSession20handle_target_is_allEON8maxscale6BufferERKNS_11RoutingPlanE+0xb8): server/modules/routing/readwritesplit/rwsplit_route_stmt.cc:157
        /usr/lib64/maxscale/libreadwritesplit.so(_ZN14RWSplitSession10route_stmtEON8maxscale6BufferERKNS_11RoutingPlanE+0x220): server/modules/routing/readwritesplit/rwsplit_route_stmt.cc:325
        /usr/lib64/maxscale/libreadwritesplit.so(_ZN14RWSplitSession11route_queryEON8maxscale6BufferE+0x1bc): server/modules/routing/readwritesplit/rwsplitsession.cc:132
        /usr/lib64/maxscale/libreadwritesplit.so(+0xc552c): server/modules/routing/readwritesplit/rwsplit_route_stmt.cc:76
        /usr/lib64/maxscale/libreadwritesplit.so(+0xca257): /opt/rh/devtoolset-9/root/usr/include/c++/9/bits/std_function.h:287
        /usr/lib64/maxscale/libmaxscale-common.so.1.0.0(_ZNKSt8functionIFbP5GWBUFEEclES1_+0x49): /opt/rh/devtoolset-9/root/usr/include/c++/9/bits/std_function.h:689
        /usr/lib64/maxscale/libmaxscale-common.so.1.0.0(+0x6ca3e3): server/core/session.cc:613
        /usr/lib64/maxscale/libmaxscale-common.so.1.0.0(+0x6d06b6): /opt/rh/devtoolset-9/root/usr/include/c++/9/bits/std_function.h:287
        /usr/lib64/maxscale/libmaxscale-common.so.1.0.0(_ZNKSt8functionIFbN7maxbase6Worker8Callable6ActionEEEclES3_+0x48): /opt/rh/devtoolset-9/root/usr/include/c++/9/bits/std_function.h:689
        /usr/lib64/maxscale/libmaxscale-common.so.1.0.0(_ZN7maxbase6Worker22DCallFunctorWithCancel7do_callENS0_8Callable6ActionE+0x24): maxutils/maxbase/include/maxbase/worker.hh:1089
        /usr/lib64/maxscale/libmaxscale-common.so.1.0.0(_ZN7maxbase6Worker5DCall4callENS0_8Callable6ActionE+0x2b): maxutils/maxbase/include/maxbase/worker.hh:928
        /usr/lib64/maxscale/libmaxscale-common.so.1.0.0(_ZN7maxbase6Worker4tickEv+0x2cf): maxutils/maxbase/src/worker.cc:1225
        /usr/lib64/maxscale/libmaxscale-common.so.1.0.0(_ZN7maxbase6Worker15DelegatingTimerIS0_E4tickEv+0x66): maxutils/maxbase/include/maxbase/worker.hh:469 (discriminator 4)
        /usr/lib64/maxscale/libmaxscale-common.so.1.0.0(_ZN7maxbase11WorkerTimer18handle_poll_eventsEPNS_6WorkerEjNS_8Pollable7ContextE+0x1b1): maxutils/maxbase/src/worker.cc:327
        /usr/lib64/maxscale/libmaxscale-common.so.1.0.0(_ZN7maxbase6Worker14deliver_eventsEmNSt6chrono10time_pointINS1_3_V212steady_clockENS1_8durationIlSt5ratioILl1ELl1000000000EEEEEEPNS_8PollableEjNSA_7ContextE+0x1b4): maxutils/maxbase/src/worker.cc:1041
        /usr/lib64/maxscale/libmaxscale-common.so.1.0.0(_ZN7maxbase6Worker15poll_waiteventsEv+0x647): maxutils/maxbase/src/worker.cc:1168
        /usr/lib64/maxscale/libmaxscale-common.so.1.0.0(_ZN7maxbase6Worker3runEPNS_9SemaphoreE+0x129): maxutils/maxbase/src/worker.cc:820
        /usr/lib64/maxscale/libmaxscale-common.so.1.0.0(_ZN7maxbase6Worker11thread_mainEPS0_PNS_9SemaphoreE+0x23): maxutils/maxbase/src/worker.cc:933
        /usr/lib64/maxscale/libmaxscale-common.so.1.0.0(_ZSt13__invoke_implIvPFvPN7maxbase6WorkerEPNS0_9SemaphoreEEJS2_S4_EET_St14__invoke_otherOT0_DpOT1_+0x4d): /opt/rh/devtoolset-9/root/usr/include/c++/9/bits/invoke.h:60
        /usr/lib64/maxscale/libmaxscale-common.so.1.0.0(_ZSt8__invokeIPFvPN7maxbase6WorkerEPNS0_9SemaphoreEEJS2_S4_EENSt15__invoke_resultIT_JDpT0_EE4typeEOS8_DpOS9_+0x4f): /opt/rh/devtoolset-9/root/usr/include/c++/9/bits/invoke.h:96
        /usr/lib64/maxscale/libmaxscale-common.so.1.0.0(_ZNSt6thread8_InvokerISt5tupleIJPFvPN7maxbase6WorkerEPNS2_9SemaphoreEES4_S6_EEE9_M_invokeIJLm0ELm1ELm2EEEEvSt12_Index_tupleIJXspT_EEE+0x5f): /opt/rh/devtoolset-9/root/usr/include/c++/9/thread:244
        /usr/lib64/maxscale/libmaxscale-common.so.1.0.0(_ZNSt6thread8_InvokerISt5tupleIJPFvPN7maxbase6WorkerEPNS2_9SemaphoreEES4_S6_EEEclEv+0x18): /opt/rh/devtoolset-9/root/usr/include/c++/9/thread:252
        /usr/lib64/maxscale/libmaxscale-common.so.1.0.0(_ZNSt6thread11_State_implINS_8_InvokerISt5tupleIJPFvPN7maxbase6WorkerEPNS3_9SemaphoreEES5_S7_EEEEE6_M_runEv+0x1c): /opt/rh/devtoolset-9/root/usr/include/c++/9/thread:195
        /usr/lib64/maxscale/libmaxscale-common.so.1.0.0(+0x85d6f0): thread48.o:?
        /lib64/libpthread.so.0(+0x7ea5): pthread_create.c:?
      

      The complete log of the test case is attached.

        Attachments

          Activity

            People

            Assignee:
            markus makela markus makela
            Reporter:
            markus makela markus makela
            Votes:
            0 Vote for this issue
            Watchers:
            1 Start watching this issue

              Dates

              Created:
              Updated:
              Resolved:

                Git Integration

                Error rendering 'com.xiplink.jira.git.jira_git_plugin:git-issue-webpanel'. Please contact your Jira administrators.