FE connection info structure migration.

Replaced INFINIDB_VTABLE.cal_conn_info with a plugin thread variable. Fixed query_string memory deallocation crash at plugin_thdvar_cleanup.
2025-08-07 03:22:57 +03:00 · 2018-12-30 07:38:39 +03:00
parent 971055a473
commit ca0240037a
10 changed files with 303 additions and 127 deletions
--- a/dbcon/mysql/ha_calpont.cpp
+++ b/dbcon/mysql/ha_calpont.cpp
@@ -380,7 +380,6 @@ static int calpont_close_connection ( handlerton* hton, THD* thd )

 ha_calpont::ha_calpont(handlerton* hton, TABLE_SHARE* table_arg) :
    handler(hton, table_arg),
-    fe_conn_info(NULL),
    int_table_flags(HA_BINLOG_STMT_CAPABLE | HA_BINLOG_ROW_CAPABLE |
                    HA_TABLE_SCAN_ON_INDEX |
                    HA_CAN_TABLE_CONDITION_PUSHDOWN)
@@ -684,11 +683,10 @@ int ha_calpont::rnd_init(bool scan)
 {
    DBUG_ENTER("ha_calpont::rnd_init");

-    // Use global THD*
-    set_original_query(current_thd, current_thd->query_string.str());
-    mcs_handler_info mhi(static_cast<void*>(this), LEGACY);    
+    String query_string_cpy; query_string_cpy.append(current_thd->query_string.str());
+    set_original_query(current_thd, query_string_cpy.c_ptr_safe());

-    int rc = ha_calpont_impl_rnd_init(table, mhi);
+    int rc = ha_calpont_impl_rnd_init(table);

    DBUG_RETURN(rc);
 }
--- a/dbcon/mysql/ha_calpont.h
+++ b/dbcon/mysql/ha_calpont.h
@@ -43,7 +43,6 @@ class ha_calpont: public handler
    THR_LOCK_DATA lock;      ///< MySQL lock
    INFINIDB_SHARE* share;    ///< Shared lock info
    ulonglong int_table_flags;
-    void* fe_conn_info;

 public:
    ha_calpont(handlerton* hton, TABLE_SHARE* table_arg);
--- a/dbcon/mysql/ha_calpont_ddl.cpp
+++ b/dbcon/mysql/ha_calpont_ddl.cpp
@@ -664,10 +664,10 @@ int ProcessDDLStatement(string& ddlStatement, string& schema, const string& tabl
    IDBCompressInterface idbCompress;
    parser.Parse(ddlStatement.c_str());

-    if (!thd->infinidb_vtable.cal_conn_info)
-        thd->infinidb_vtable.cal_conn_info = (void*)(new cal_connection_info());
+    if (get_fe_conn_info_ptr() == NULL)
+        set_fe_conn_info_ptr((void*)new cal_connection_info());

-    cal_connection_info* ci = reinterpret_cast<cal_connection_info*>(thd->infinidb_vtable.cal_conn_info);
+    cal_connection_info* ci = reinterpret_cast<cal_connection_info*>(get_fe_conn_info_ptr());

    if (parser.Good())
    {
--- a/dbcon/mysql/ha_calpont_execplan.cpp
+++ b/dbcon/mysql/ha_calpont_execplan.cpp
@@ -58,6 +58,7 @@ using namespace logging;
 #include "idb_mysql.h"

 #include "ha_calpont_impl_if.h"
+#include "mcs_sysvars.h"
 #include "ha_subquery.h"
 //#include "ha_view.h"
 using namespace cal_impl_if;
@@ -1442,10 +1443,10 @@ bool buildPredicateItem(Item_func* ifp, gp_walk_info* gwip)
        }
    }

-    if (!(gwip->thd->infinidb_vtable.cal_conn_info))
-        gwip->thd->infinidb_vtable.cal_conn_info = (void*)(new cal_connection_info());
+    if (get_fe_conn_info_ptr() == NULL)
+        set_fe_conn_info_ptr((void*)new cal_connection_info());

-    cal_connection_info* ci = reinterpret_cast<cal_connection_info*>(gwip->thd->infinidb_vtable.cal_conn_info);
+    cal_connection_info* ci = reinterpret_cast<cal_connection_info*>(get_fe_conn_info_ptr());


    if (ifp->functype() == Item_func::BETWEEN)
@@ -2466,10 +2467,10 @@ void setError(THD* thd, uint32_t errcode, string errmsg)
    thd->infinidb_vtable.override_largeside_estimate = false;

    // reset expressionID
-    if (!(thd->infinidb_vtable.cal_conn_info))
-        thd->infinidb_vtable.cal_conn_info = (void*)(new cal_connection_info());
+    if (get_fe_conn_info_ptr() == NULL)
+        set_fe_conn_info_ptr((void*)new cal_connection_info());

-    cal_connection_info* ci = reinterpret_cast<cal_connection_info*>(thd->infinidb_vtable.cal_conn_info);
+    cal_connection_info* ci = reinterpret_cast<cal_connection_info*>(get_fe_conn_info_ptr());
    ci->expressionId = 0;
 }

@@ -3104,10 +3105,10 @@ ArithmeticColumn* buildArithmeticColumn(
    bool& nonSupport,
    bool pushdownHand)
 {
-    if (!(gwi.thd->infinidb_vtable.cal_conn_info))
-        gwi.thd->infinidb_vtable.cal_conn_info = (void*)(new cal_connection_info());
+    if (get_fe_conn_info_ptr() == NULL)
+        set_fe_conn_info_ptr((void*)new cal_connection_info());

-    cal_connection_info* ci = reinterpret_cast<cal_connection_info*>(gwi.thd->infinidb_vtable.cal_conn_info);
+    cal_connection_info* ci = reinterpret_cast<cal_connection_info*>(get_fe_conn_info_ptr());

    ArithmeticColumn* ac = new ArithmeticColumn();
    Item** sfitempp = item->arguments();
@@ -3329,10 +3330,10 @@ ReturnedColumn* buildFunctionColumn(
    bool& nonSupport,
    bool pushdownHand)
 {
-    if (!(gwi.thd->infinidb_vtable.cal_conn_info))
-        gwi.thd->infinidb_vtable.cal_conn_info = (void*)(new cal_connection_info());
+    if (get_fe_conn_info_ptr() == NULL)
+        set_fe_conn_info_ptr((void*)new cal_connection_info());

-    cal_connection_info* ci = reinterpret_cast<cal_connection_info*>(gwi.thd->infinidb_vtable.cal_conn_info);
+    cal_connection_info* ci = reinterpret_cast<cal_connection_info*>(get_fe_conn_info_ptr());

    string funcName = ifp->func_name();
    FuncExp* funcExp = FuncExp::instance();
@@ -3801,10 +3802,10 @@ ReturnedColumn* buildFunctionColumn(

 FunctionColumn* buildCaseFunction(Item_func* item, gp_walk_info& gwi, bool& nonSupport)
 {
-    if (!(gwi.thd->infinidb_vtable.cal_conn_info))
-        gwi.thd->infinidb_vtable.cal_conn_info = (void*)(new cal_connection_info());
+    if (get_fe_conn_info_ptr() == NULL)
+        set_fe_conn_info_ptr((void*)new cal_connection_info());

-    cal_connection_info* ci = reinterpret_cast<cal_connection_info*>(gwi.thd->infinidb_vtable.cal_conn_info);
+    cal_connection_info* ci = reinterpret_cast<cal_connection_info*>(get_fe_conn_info_ptr());

    FunctionColumn* fc = new FunctionColumn();
    FunctionParm funcParms;
@@ -4194,10 +4195,10 @@ ReturnedColumn* buildAggregateColumn(Item* item, gp_walk_info& gwi)
    vector<SRCP> selCols;
    vector<SRCP> orderCols;
    bool bIsConst = false;
-    if (!(gwi.thd->infinidb_vtable.cal_conn_info))
-        gwi.thd->infinidb_vtable.cal_conn_info = (void*)(new cal_connection_info());
+    if (get_fe_conn_info_ptr() == NULL)
+        set_fe_conn_info_ptr((void*)new cal_connection_info());

-    cal_connection_info* ci = reinterpret_cast<cal_connection_info*>(gwi.thd->infinidb_vtable.cal_conn_info);
+    cal_connection_info* ci = reinterpret_cast<cal_connection_info*>(get_fe_conn_info_ptr());

    Item_sum* isp = reinterpret_cast<Item_sum*>(item);
    Item** sfitempp = isp->get_orig_args();
--- a/dbcon/mysql/ha_calpont_impl.cpp
+++ b/dbcon/mysql/ha_calpont_impl.cpp
@@ -866,10 +866,10 @@ void makeUpdateSemiJoin(const ParseTree* n, void* obj)

 uint32_t doUpdateDelete(THD* thd)
 {
-    if (!thd->infinidb_vtable.cal_conn_info)
-        thd->infinidb_vtable.cal_conn_info = (void*)(new cal_connection_info());
+    if (get_fe_conn_info_ptr() == NULL)
+        set_fe_conn_info_ptr((void*)new cal_connection_info());

-    cal_connection_info* ci = reinterpret_cast<cal_connection_info*>(thd->infinidb_vtable.cal_conn_info);
+    cal_connection_info* ci = reinterpret_cast<cal_connection_info*>(get_fe_conn_info_ptr());

    //@bug 5660. Error out DDL/DML on slave node, or on local query node
    if (ci->isSlaveNode && !thd->slave_thread)
@@ -1919,10 +1919,10 @@ extern "C"
    {
        THD* thd = current_thd;

-        if (!thd->infinidb_vtable.cal_conn_info)
-            thd->infinidb_vtable.cal_conn_info = (void*)(new cal_connection_info());
+        if (get_fe_conn_info_ptr() == NULL)
+            set_fe_conn_info_ptr((void*)new cal_connection_info());

-        cal_connection_info* ci = reinterpret_cast<cal_connection_info*>(thd->infinidb_vtable.cal_conn_info);
+        cal_connection_info* ci = reinterpret_cast<cal_connection_info*>(get_fe_conn_info_ptr());

        unsigned long l = ci->queryStats.size();

@@ -1971,10 +1971,10 @@ extern "C"
    {
        THD* thd = current_thd;

-        if (!thd->infinidb_vtable.cal_conn_info)
-            thd->infinidb_vtable.cal_conn_info = (void*)(new cal_connection_info());
+        if (get_fe_conn_info_ptr() == NULL)
+            set_fe_conn_info_ptr((void*)new cal_connection_info());

-        cal_connection_info* ci = reinterpret_cast<cal_connection_info*>(thd->infinidb_vtable.cal_conn_info);
+        cal_connection_info* ci = reinterpret_cast<cal_connection_info*>(get_fe_conn_info_ptr());

        long long oldTrace = ci->traceFlags;
        ci->traceFlags = (uint32_t)(*((long long*)args->args[0]));
@@ -2329,10 +2329,10 @@ extern "C"
    {
        THD* thd = current_thd;

-        if (!thd->infinidb_vtable.cal_conn_info)
-            thd->infinidb_vtable.cal_conn_info = (void*)(new cal_connection_info());
+        if (get_fe_conn_info_ptr() == NULL)
+            set_fe_conn_info_ptr((void*)new cal_connection_info());

-        cal_connection_info* ci = reinterpret_cast<cal_connection_info*>(thd->infinidb_vtable.cal_conn_info);
+        cal_connection_info* ci = reinterpret_cast<cal_connection_info*>(get_fe_conn_info_ptr());
        CalpontSystemCatalog::TableName tableName;

        if ( args->arg_count == 2 )
@@ -2402,11 +2402,11 @@ extern "C"
    {
        THD* thd = current_thd;

-        if (!thd->infinidb_vtable.cal_conn_info)
-            thd->infinidb_vtable.cal_conn_info = (void*)(new cal_connection_info());
+        if (get_fe_conn_info_ptr() == NULL)
+            set_fe_conn_info_ptr((void*)new cal_connection_info());

        cal_connection_info* ci = reinterpret_cast<cal_connection_info*>(
-                                      thd->infinidb_vtable.cal_conn_info);
+                                      get_fe_conn_info_ptr());
        long long lockID = *reinterpret_cast<long long*>(args->args[0]);

        if ( !ci->dmlProc )
@@ -2581,10 +2581,10 @@ extern "C"
            }
        }

-        if (!thd->infinidb_vtable.cal_conn_info)
-            thd->infinidb_vtable.cal_conn_info = (void*)(new cal_connection_info());
+        if (get_fe_conn_info_ptr() == NULL)
+            set_fe_conn_info_ptr((void*)new cal_connection_info());

-        cal_connection_info* ci = reinterpret_cast<cal_connection_info*>(thd->infinidb_vtable.cal_conn_info);
+        cal_connection_info* ci = reinterpret_cast<cal_connection_info*>(get_fe_conn_info_ptr());

        if (flags > 0)
            //msgp = &connMap[sessionID].extendedStats;
@@ -2677,10 +2677,10 @@ extern "C"
    {
        THD* thd = current_thd;

-        if (!thd->infinidb_vtable.cal_conn_info)
-            thd->infinidb_vtable.cal_conn_info = (void*)(new cal_connection_info());
+        if (get_fe_conn_info_ptr() == NULL)
+            set_fe_conn_info_ptr((void*)new cal_connection_info());

-        cal_connection_info* ci = reinterpret_cast<cal_connection_info*>(thd->infinidb_vtable.cal_conn_info);
+        cal_connection_info* ci = reinterpret_cast<cal_connection_info*>(get_fe_conn_info_ptr());
        idbassert(ci != 0);

        MessageQueueClient* mqc = 0;
@@ -2768,14 +2768,8 @@ int ha_calpont_impl_discover_existence(const char* schema, const char* name)
    return 0;
 }

-int ha_calpont_impl_rnd_init(TABLE* table, mcs_handler_info hndtl_ptr)
+int ha_calpont_impl_rnd_init(TABLE* table)
 {
-    ha_calpont* handler;
-    if ( hndtl_ptr.hndl_type == LEGACY )
-    {
-        handler = reinterpret_cast<ha_calpont*>(hndtl_ptr.hndl_ptr);
-    }
-    
 #ifdef DEBUG_SETENV
    string home(getenv("HOME"));

@@ -2874,10 +2868,10 @@ int ha_calpont_impl_rnd_init(TABLE* table, mcs_handler_info hndtl_ptr)
    boost::shared_ptr<CalpontSystemCatalog> csc = CalpontSystemCatalog::makeCalpontSystemCatalog(sessionID);
    csc->identity(CalpontSystemCatalog::FE);

-    if (!thd->infinidb_vtable.cal_conn_info)
-        thd->infinidb_vtable.cal_conn_info = (void*)(new cal_connection_info());
+    if (get_fe_conn_info_ptr() == NULL)
+        set_fe_conn_info_ptr((void*)new cal_connection_info());

-    cal_connection_info* ci = reinterpret_cast<cal_connection_info*>(thd->infinidb_vtable.cal_conn_info);
+    cal_connection_info* ci = reinterpret_cast<cal_connection_info*>(get_fe_conn_info_ptr());

    idbassert(ci != 0);

@@ -3413,10 +3407,10 @@ int ha_calpont_impl_rnd_next(uchar* buf, TABLE* table)
        return ER_INTERNAL_ERROR;
    }

-    if (!thd->infinidb_vtable.cal_conn_info)
-        thd->infinidb_vtable.cal_conn_info = (void*)(new cal_connection_info());
+    if (get_fe_conn_info_ptr() == NULL)
+        set_fe_conn_info_ptr((void*)new cal_connection_info());

-    cal_connection_info* ci = reinterpret_cast<cal_connection_info*>(thd->infinidb_vtable.cal_conn_info);
+    cal_connection_info* ci = reinterpret_cast<cal_connection_info*>(get_fe_conn_info_ptr());

    // @bug 3078
    if (thd->killed == KILL_QUERY || thd->killed == KILL_QUERY_HARD)
@@ -3514,8 +3508,8 @@ int ha_calpont_impl_rnd_end(TABLE* table)

    thd->infinidb_vtable.isNewQuery = true;

-    if (thd->infinidb_vtable.cal_conn_info)
-        ci = reinterpret_cast<cal_connection_info*>(thd->infinidb_vtable.cal_conn_info);
+    if (get_fe_conn_info_ptr() != NULL)
+        ci = reinterpret_cast<cal_connection_info*>(get_fe_conn_info_ptr());

    if (thd->infinidb_vtable.vtable_state == THD::INFINIDB_ORDER_BY )
    {
@@ -3563,8 +3557,8 @@ int ha_calpont_impl_rnd_end(TABLE* table)

    if (!ci)
    {
-        thd->infinidb_vtable.cal_conn_info = (void*)(new cal_connection_info());
-        ci = reinterpret_cast<cal_connection_info*>(thd->infinidb_vtable.cal_conn_info);
+        set_fe_conn_info_ptr((void*)new cal_connection_info());
+        ci = reinterpret_cast<cal_connection_info*>(get_fe_conn_info_ptr());
    }

    // @bug 3078. Also session limit variable works the same as ctrl+c
@@ -3684,10 +3678,10 @@ int ha_calpont_impl_create(const char* name, TABLE* table_arg, HA_CREATE_INFO* c
 {
    THD* thd = current_thd;

-    if (!thd->infinidb_vtable.cal_conn_info)
-        thd->infinidb_vtable.cal_conn_info = (void*)(new cal_connection_info());
+    if (get_fe_conn_info_ptr() == NULL)
+        set_fe_conn_info_ptr((void*)new cal_connection_info());

-    cal_connection_info* ci = reinterpret_cast<cal_connection_info*>(thd->infinidb_vtable.cal_conn_info);
+    cal_connection_info* ci = reinterpret_cast<cal_connection_info*>(get_fe_conn_info_ptr());

    // @bug1940 Do nothing for select query. Support of set default engine to IDB.
    if (thd->infinidb_vtable.vtable_state == THD::INFINIDB_CREATE_VTABLE ||
@@ -3733,10 +3727,10 @@ int ha_calpont_impl_delete_table(const char* name)
    if (string(name).find("@0024vtable") != string::npos)
        return 0;

-    if (!thd->infinidb_vtable.cal_conn_info)
-        thd->infinidb_vtable.cal_conn_info = (void*)(new cal_connection_info());
+    if (get_fe_conn_info_ptr() == NULL)
+        set_fe_conn_info_ptr((void*)new cal_connection_info());

-    cal_connection_info* ci = reinterpret_cast<cal_connection_info*>(thd->infinidb_vtable.cal_conn_info);
+    cal_connection_info* ci = reinterpret_cast<cal_connection_info*>(get_fe_conn_info_ptr());

    if (!thd) return 0;

@@ -3809,10 +3803,10 @@ int ha_calpont_impl_write_row(uchar* buf, TABLE* table)
        }
    }

-    if (!thd->infinidb_vtable.cal_conn_info)
-        thd->infinidb_vtable.cal_conn_info = (void*)(new cal_connection_info());
+    if (get_fe_conn_info_ptr() == NULL)
+        set_fe_conn_info_ptr((void*)new cal_connection_info());

-    cal_connection_info* ci = reinterpret_cast<cal_connection_info*>(thd->infinidb_vtable.cal_conn_info);
+    cal_connection_info* ci = reinterpret_cast<cal_connection_info*>(get_fe_conn_info_ptr());

    if (thd->slave_thread) return 0;

@@ -3855,10 +3849,10 @@ int ha_calpont_impl_update_row()
    //@Bug 2540. Return the correct error code.
    THD* thd = current_thd;

-    if (!thd->infinidb_vtable.cal_conn_info)
-        thd->infinidb_vtable.cal_conn_info = (void*)(new cal_connection_info());
+    if (get_fe_conn_info_ptr() == NULL)
+        set_fe_conn_info_ptr((void*)new cal_connection_info());

-    cal_connection_info* ci = reinterpret_cast<cal_connection_info*>(thd->infinidb_vtable.cal_conn_info);
+    cal_connection_info* ci = reinterpret_cast<cal_connection_info*>(get_fe_conn_info_ptr());
    int rc = ci->rc;

    if ( rc != 0 )
@@ -3872,10 +3866,10 @@ int ha_calpont_impl_delete_row()
    //@Bug 2540. Return the correct error code.
    THD* thd = current_thd;

-    if (!thd->infinidb_vtable.cal_conn_info)
-        thd->infinidb_vtable.cal_conn_info = (void*)(new cal_connection_info());
+    if (get_fe_conn_info_ptr() == NULL)
+        set_fe_conn_info_ptr((void*)new cal_connection_info());

-    cal_connection_info* ci = reinterpret_cast<cal_connection_info*>(thd->infinidb_vtable.cal_conn_info);
+    cal_connection_info* ci = reinterpret_cast<cal_connection_info*>(get_fe_conn_info_ptr());
    int rc = ci->rc;

    if ( rc != 0 )
@@ -3888,10 +3882,10 @@ void ha_calpont_impl_start_bulk_insert(ha_rows rows, TABLE* table)
 {
    THD* thd = current_thd;

-    if (!thd->infinidb_vtable.cal_conn_info)
-        thd->infinidb_vtable.cal_conn_info = (void*)(new cal_connection_info());
+    if (get_fe_conn_info_ptr() == NULL)
+        set_fe_conn_info_ptr((void*)new cal_connection_info());

-    cal_connection_info* ci = reinterpret_cast<cal_connection_info*>(thd->infinidb_vtable.cal_conn_info);
+    cal_connection_info* ci = reinterpret_cast<cal_connection_info*>(get_fe_conn_info_ptr());

    // clear rows variable
    ci->rowsHaveInserted = 0;
@@ -4456,10 +4450,10 @@ int ha_calpont_impl_end_bulk_insert(bool abort, TABLE* table)

    std::string aTmpDir(startup::StartUp::tmpDir());

-    if (!thd->infinidb_vtable.cal_conn_info)
-        thd->infinidb_vtable.cal_conn_info = (void*)(new cal_connection_info());
+    if (get_fe_conn_info_ptr() == NULL)
+        set_fe_conn_info_ptr((void*)new cal_connection_info());

-    cal_connection_info* ci = reinterpret_cast<cal_connection_info*>(thd->infinidb_vtable.cal_conn_info);
+    cal_connection_info* ci = reinterpret_cast<cal_connection_info*>(get_fe_conn_info_ptr());

    if (thd->slave_thread) return 0;

@@ -4714,10 +4708,10 @@ int ha_calpont_impl_commit (handlerton* hton, THD* thd, bool all)
            thd->infinidb_vtable.vtable_state == THD::INFINIDB_REDO_PHASE1)
        return 0;

-    if (!thd->infinidb_vtable.cal_conn_info)
-        thd->infinidb_vtable.cal_conn_info = (void*)(new cal_connection_info());
+    if (get_fe_conn_info_ptr() == NULL)
+        set_fe_conn_info_ptr((void*)new cal_connection_info());

-    cal_connection_info* ci = reinterpret_cast<cal_connection_info*>(thd->infinidb_vtable.cal_conn_info);
+    cal_connection_info* ci = reinterpret_cast<cal_connection_info*>(get_fe_conn_info_ptr());

    if (ci->isAlter)
        return 0;
@@ -4755,10 +4749,10 @@ int ha_calpont_impl_rollback (handlerton* hton, THD* thd, bool all)
    //	return 0;
    //}

-    if (!thd->infinidb_vtable.cal_conn_info)
-        thd->infinidb_vtable.cal_conn_info = (void*)(new cal_connection_info());
+    if (get_fe_conn_info_ptr() == NULL)
+        set_fe_conn_info_ptr((void*)new cal_connection_info());

-    cal_connection_info* ci = reinterpret_cast<cal_connection_info*>(thd->infinidb_vtable.cal_conn_info);
+    cal_connection_info* ci = reinterpret_cast<cal_connection_info*>(get_fe_conn_info_ptr());

    if ( !ci->dmlProc )
    {
@@ -4785,10 +4779,10 @@ int ha_calpont_impl_close_connection (handlerton* hton, THD* thd)

    execplan::CalpontSystemCatalog::removeCalpontSystemCatalog(tid2sid(thd->thread_id));

-    if (!thd->infinidb_vtable.cal_conn_info)
-        thd->infinidb_vtable.cal_conn_info = (void*)(new cal_connection_info());
+    if (get_fe_conn_info_ptr() == NULL)
+        set_fe_conn_info_ptr((void*)new cal_connection_info());

-    cal_connection_info* ci = reinterpret_cast<cal_connection_info*>(thd->infinidb_vtable.cal_conn_info);
+    cal_connection_info* ci = reinterpret_cast<cal_connection_info*>(get_fe_conn_info_ptr());

    if (!ci) return 0;

@@ -4815,10 +4809,10 @@ int ha_calpont_impl_rename_table(const char* from, const char* to)
    IDEBUG( cout << "ha_calpont_impl_rename_table: " << from << " => " << to << endl );
    THD* thd = current_thd;

-    if (!thd->infinidb_vtable.cal_conn_info)
-        thd->infinidb_vtable.cal_conn_info = (void*)(new cal_connection_info());
+    if (get_fe_conn_info_ptr() == NULL)
+        set_fe_conn_info_ptr((void*)new cal_connection_info());

-    cal_connection_info* ci = reinterpret_cast<cal_connection_info*>(thd->infinidb_vtable.cal_conn_info);
+    cal_connection_info* ci = reinterpret_cast<cal_connection_info*>(get_fe_conn_info_ptr());

    //@Bug 1948. Alter table call rename table twice
    if ( ci->alterTableState == cal_connection_info::ALTER_FIRST_RENAME )
@@ -4866,10 +4860,10 @@ COND* ha_calpont_impl_cond_push(COND* cond, TABLE* table)
    alias.assign(table->alias.ptr(), table->alias.length());
    IDEBUG( cout << "ha_calpont_impl_cond_push: " << alias << endl );

-    if (!thd->infinidb_vtable.cal_conn_info)
-        thd->infinidb_vtable.cal_conn_info = (void*)(new cal_connection_info());
+    if (get_fe_conn_info_ptr() == NULL)
+        set_fe_conn_info_ptr((void*)new cal_connection_info());

-    cal_connection_info* ci = reinterpret_cast<cal_connection_info*>(thd->infinidb_vtable.cal_conn_info);
+    cal_connection_info* ci = reinterpret_cast<cal_connection_info*>(get_fe_conn_info_ptr());

    cal_table_info ti = ci->tableMap[table];

@@ -4947,10 +4941,10 @@ int ha_calpont_impl_external_lock(THD* thd, TABLE* table, int lock_type)
    if ( thd->infinidb_vtable.vtable_state == THD::INFINIDB_INIT  )
        return 0;

-    if (!thd->infinidb_vtable.cal_conn_info)
-        thd->infinidb_vtable.cal_conn_info = (void*)(new cal_connection_info());
+    if (get_fe_conn_info_ptr() == NULL)
+        set_fe_conn_info_ptr((void*)new cal_connection_info());

-    cal_connection_info* ci = reinterpret_cast<cal_connection_info*>(thd->infinidb_vtable.cal_conn_info);
+    cal_connection_info* ci = reinterpret_cast<cal_connection_info*>(get_fe_conn_info_ptr());

    if (thd->killed == KILL_QUERY || thd->killed == KILL_QUERY_HARD)
    {
@@ -5112,10 +5106,10 @@ int ha_calpont_impl_group_by_init(ha_calpont_group_by_handler* group_hand, TABLE
    boost::shared_ptr<CalpontSystemCatalog> csc = CalpontSystemCatalog::makeCalpontSystemCatalog(sessionID);
    csc->identity(CalpontSystemCatalog::FE);

-    if (!thd->infinidb_vtable.cal_conn_info)
-        thd->infinidb_vtable.cal_conn_info = (void*)(new cal_connection_info());
+    if (get_fe_conn_info_ptr() == NULL)
+        set_fe_conn_info_ptr((void*)new cal_connection_info());

-    cal_connection_info* ci = reinterpret_cast<cal_connection_info*>(thd->infinidb_vtable.cal_conn_info);
+    cal_connection_info* ci = reinterpret_cast<cal_connection_info*>(get_fe_conn_info_ptr());

    idbassert(ci != 0);

@@ -5614,10 +5608,10 @@ int ha_calpont_impl_group_by_next(ha_calpont_group_by_handler* group_hand, TABLE
        return ER_INTERNAL_ERROR;
    }
    */
-    if (!thd->infinidb_vtable.cal_conn_info)
-        thd->infinidb_vtable.cal_conn_info = (void*)(new cal_connection_info());
+    if (get_fe_conn_info_ptr() == NULL)
+        set_fe_conn_info_ptr((void*)new cal_connection_info());

-    cal_connection_info* ci = reinterpret_cast<cal_connection_info*>(thd->infinidb_vtable.cal_conn_info);
+    cal_connection_info* ci = reinterpret_cast<cal_connection_info*>(get_fe_conn_info_ptr());

    // @bug 3078
    if (thd->killed == KILL_QUERY || thd->killed == KILL_QUERY_HARD)
@@ -5718,8 +5712,8 @@ int ha_calpont_impl_group_by_end(ha_calpont_group_by_handler* group_hand, TABLE*
    thd->infinidb_vtable.isNewQuery = true;
    thd->infinidb_vtable.isUnion = false;

-    if (thd->infinidb_vtable.cal_conn_info)
-        ci = reinterpret_cast<cal_connection_info*>(thd->infinidb_vtable.cal_conn_info);
+    if (get_fe_conn_info_ptr() != NULL)
+        ci = reinterpret_cast<cal_connection_info*>(get_fe_conn_info_ptr());

    // MCOL-1052
    //if (thd->infinidb_vtable.vtable_state == THD::INFINIDB_ORDER_BY )
@@ -5756,8 +5750,8 @@ int ha_calpont_impl_group_by_end(ha_calpont_group_by_handler* group_hand, TABLE*

    if (!ci)
    {
-        thd->infinidb_vtable.cal_conn_info = (void*)(new cal_connection_info());
-        ci = reinterpret_cast<cal_connection_info*>(thd->infinidb_vtable.cal_conn_info);
+        set_fe_conn_info_ptr((void*)new cal_connection_info());
+        ci = reinterpret_cast<cal_connection_info*>(get_fe_conn_info_ptr());
    }

    // @bug 3078. Also session limit variable works the same as ctrl+c
--- a/dbcon/mysql/ha_calpont_impl.h
+++ b/dbcon/mysql/ha_calpont_impl.h
@@ -27,7 +27,7 @@ extern int ha_calpont_impl_create(const char* name, TABLE* table_arg, HA_CREATE_
 extern int ha_calpont_impl_delete_table(const char* name);
 extern int ha_calpont_impl_open(const char* name, int mode, uint32_t test_if_locked);
 extern int ha_calpont_impl_close(void);
-extern int ha_calpont_impl_rnd_init(TABLE* table, mcs_handler_info hndtl_ptr);
+extern int ha_calpont_impl_rnd_init(TABLE* table);
 extern int ha_calpont_impl_rnd_next(uchar* buf, TABLE* table);
 extern int ha_calpont_impl_rnd_end(TABLE* table);
 extern int ha_calpont_impl_write_row(uchar* buf, TABLE* table);
--- a/dbcon/mysql/ha_pseudocolumn.cpp
+++ b/dbcon/mysql/ha_pseudocolumn.cpp
@@ -20,6 +20,7 @@ using namespace execplan;
 #include "functor_str.h"

 #include "ha_calpont_impl_if.h"
+#include "mcs_sysvars.h"
 using namespace cal_impl_if;

 namespace
@@ -54,10 +55,10 @@ int64_t idblocalpm()
 {
    THD* thd = current_thd;

-    if (!thd->infinidb_vtable.cal_conn_info)
-        thd->infinidb_vtable.cal_conn_info = (void*)(new cal_connection_info());
+    if (get_fe_conn_info_ptr() == NULL)
+        set_fe_conn_info_ptr((void*)new cal_connection_info());

-    cal_connection_info* ci = reinterpret_cast<cal_connection_info*>(thd->infinidb_vtable.cal_conn_info);
+    cal_connection_info* ci = reinterpret_cast<cal_connection_info*>(get_fe_conn_info_ptr());

    if (ci->localPm == -1)
    {
@@ -485,10 +486,10 @@ execplan::ReturnedColumn* buildPseudoColumn(Item* item,
        bool& nonSupport,
        uint32_t pseudoType)
 {
-    if (!(gwi.thd->infinidb_vtable.cal_conn_info))
-        gwi.thd->infinidb_vtable.cal_conn_info = (void*)(new cal_connection_info());
+    if (get_fe_conn_info_ptr() == NULL)
+        set_fe_conn_info_ptr((void*)new cal_connection_info());

-    cal_connection_info* ci = reinterpret_cast<cal_connection_info*>(gwi.thd->infinidb_vtable.cal_conn_info);
+    cal_connection_info* ci = reinterpret_cast<cal_connection_info*>(get_fe_conn_info_ptr());

    Item_func* ifp = (Item_func*)item;

--- a/dbcon/mysql/ha_window_function.cpp
+++ b/dbcon/mysql/ha_window_function.cpp
@@ -28,6 +28,7 @@ using namespace std;

 #include "idb_mysql.h"
 #include "ha_calpont_impl_if.h"
+#include "mcs_sysvars.h"

 #include "arithmeticcolumn.h"
 #include "arithmeticoperator.h"
@@ -93,10 +94,10 @@ WF_FRAME frame(Window_frame_bound::Bound_precedence_type bound, Item* offset)
 }
 ReturnedColumn* buildBoundExp(WF_Boundary& bound, SRCP& order, gp_walk_info& gwi)
 {
-    if (!(gwi.thd->infinidb_vtable.cal_conn_info))
-        gwi.thd->infinidb_vtable.cal_conn_info = (void*)(new cal_connection_info());
+    if (get_fe_conn_info_ptr() == NULL)
+        set_fe_conn_info_ptr((void*)new cal_connection_info());

-    cal_connection_info* ci = reinterpret_cast<cal_connection_info*>(gwi.thd->infinidb_vtable.cal_conn_info);
+    cal_connection_info* ci = reinterpret_cast<cal_connection_info*>(get_fe_conn_info_ptr());

    bool addOp = true;
    ReturnedColumn* rc = NULL;
@@ -337,10 +338,10 @@ ReturnedColumn* buildWindowFunctionColumn(Item* item, gp_walk_info& gwi, bool& n
    //String str;
    //item->print(&str, QT_INFINIDB_NO_QUOTE);
    //cout << str.c_ptr() << endl;
-    if (!(gwi.thd->infinidb_vtable.cal_conn_info))
-        gwi.thd->infinidb_vtable.cal_conn_info = (void*)(new cal_connection_info());
+    if (get_fe_conn_info_ptr() == NULL)
+        set_fe_conn_info_ptr((void*)new cal_connection_info());

-    cal_connection_info* ci = reinterpret_cast<cal_connection_info*>(gwi.thd->infinidb_vtable.cal_conn_info);
+    cal_connection_info* ci = reinterpret_cast<cal_connection_info*>(get_fe_conn_info_ptr());

    gwi.hasWindowFunc = true;
    Item_window_func* wf = (Item_window_func*)item;
--- a/dbcon/mysql/mcs_sysvars.cpp
+++ b/dbcon/mysql/mcs_sysvars.cpp
@@ -0,0 +1,124 @@
+/* Copyright (C) 2014 InfiniDB, Inc.
+   Copyright (C) 2016 MariaDB Corporaton
+
+   This program is free software; you can redistribute it and/or
+   modify it under the terms of the GNU General Public License
+   as published by the Free Software Foundation; version 2 of
+   the License.
+
+   This program is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+   GNU General Public License for more details.
+
+   You should have received a copy of the GNU General Public License
+   along with this program; if not, write to the Free Software
+   Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston,
+   MA 02110-1301, USA. */
+
+#include <my_config.h>
+#include "idb_mysql.h"
+#include "mcs_sysvars.h"
+
+const char* mcs_compression_type_names[] = {
+    "NO_COMPRESSION",
+    "SNAPPY",
+    NullS
+};
+
+static TYPELIB mcs_compression_type_names_lib = {
+    array_elements(mcs_compression_type_names) - 1,
+    "mcs_compression_type_names",
+    mcs_compression_type_names,
+    NULL
+};
+
+// compression type
+static MYSQL_THDVAR_ENUM(
+    compression_type,
+    PLUGIN_VAR_RQCMDARG,
+    "Controls compression type for create tables. Possible values are: "
+    "NO_COMPRESSION segment files aren't compressed; "
+    "SNAPPY segment files are Snappy compressed (default);",
+    NULL,
+    NULL,
+    SNAPPY,
+    &mcs_compression_type_names_lib);
+
+// original query
+static MYSQL_THDVAR_STR(
+  original_query, /* name */
+  PLUGIN_VAR_MEMALLOC |
+  PLUGIN_VAR_RQCMDARG,
+  "Original query text", /* comment */
+  NULL, /* check */
+  NULL, /* update */
+  NULL /* def */
+);
+
+// fe_conn_info pointer
+static MYSQL_THDVAR_ULONGLONG(
+    fe_conn_info_ptr,
+    PLUGIN_VAR_NOSYSVAR | PLUGIN_VAR_NOCMDOPT,
+    "FrontEnd connection structure pointer. For internal usage.",
+    NULL,
+    NULL,
+    0,
+    0,
+    ~0U,
+    1
+);
+
+st_mysql_sys_var* mcs_system_variables[] =
+{
+  MYSQL_SYSVAR(compression_type),
+  MYSQL_SYSVAR(original_query),
+  MYSQL_SYSVAR(fe_conn_info_ptr),
+  NULL
+};
+
+const char* get_original_query(THD* thd) {
+    return THDVAR(thd, original_query);
+}
+
+void set_original_query(THD* thd, char* query) {
+    THDVAR(thd, original_query) = query;
+}
+
+void* get_fe_conn_info_ptr()
+{
+    return ( current_thd == NULL ) ? NULL :
+        (void*)THDVAR(current_thd, fe_conn_info_ptr);
+}
+
+void set_fe_conn_info_ptr(void* ptr)
+{
+    if ( current_thd == NULL )
+    {
+        return;
+    }
+    
+    THDVAR(current_thd, fe_conn_info_ptr) = (uint64_t)(ptr);
+}
+
+/*ha_calpont* get_legacy_handler(mcs_handler_info mcs_hndl_ptr)
+{
+    //MCOL-1101 Add handler type check
+    //hndl_ptr.hndl_type == LEGACY )
+    ha_calpont* hndl;
+    if ( mcs_hndl_ptr.hndl_ptr != NULL )
+    {
+        hndl = (ha_calpont*)(mcs_hndl_ptr.hndl_ptr);
+    }
+    else
+    {
+        hndl = new ha_calpont();
+        hndl->fe_conn_info = (void*)THDVAR(current_thd, fe_conn_info_ptr);
+    }
+    
+    return hndl;
+}*/
+
+mcs_compression_type_t get_compression_type(THD* thd) {
+    return (mcs_compression_type_t) THDVAR(thd, compression_type);
+}
--- a/dbcon/mysql/mcs_sysvars.h
+++ b/dbcon/mysql/mcs_sysvars.h
@@ -0,0 +1,58 @@
+/* Copyright (C) 2014 InfiniDB, Inc.
+   Copyright (C) 2016 MariaDB Corporaton
+
+   This program is free software; you can redistribute it and/or
+   modify it under the terms of the GNU General Public License
+   as published by the Free Software Foundation; version 2 of
+   the License.
+
+   This program is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+   GNU General Public License for more details.
+
+   You should have received a copy of the GNU General Public License
+   along with this program; if not, write to the Free Software
+   Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston,
+   MA 02110-1301, USA. */
+
+#ifndef MCS_SYSVARS_H__
+#define MCS_SYSVARS_H__
+
+#include <my_config.h>
+#include "idb_mysql.h"
+
+extern st_mysql_sys_var* mcs_system_variables[];
+
+enum mcs_handler_types_t
+{
+    SELECT,
+    GROUP_BY,
+    LEGACY
+};
+
+struct mcs_handler_info
+{
+    mcs_handler_info() : hndl_ptr(NULL), hndl_type(LEGACY) { };
+    mcs_handler_info(mcs_handler_types_t type) : hndl_ptr(NULL), hndl_type(type) { };
+    mcs_handler_info(void* ptr, mcs_handler_types_t type) : hndl_ptr(ptr), hndl_type(type) { };
+    ~mcs_handler_info() { };
+    void* hndl_ptr;
+    mcs_handler_types_t hndl_type;
+};
+
+// compression_type
+enum mcs_compression_type_t {
+    NO_COMPRESSION = 0,
+    SNAPPY = 2
+};
+
+// simple setters/getters
+const char* get_original_query(THD* thd);
+void set_original_query(THD* thd, char* query);
+mcs_compression_type_t get_compression_type(THD* thd);
+
+void* get_fe_conn_info_ptr();
+void set_fe_conn_info_ptr(void* ptr);
+
+#endif