diff --git a/azure-pipelines.yml b/azure-pipelines.yml
index a5d636ad..4444203f 100644
--- a/azure-pipelines.yml
+++ b/azure-pipelines.yml
@@ -105,7 +105,7 @@ jobs:
       docker pull mcr.microsoft.com/mssql/server:2017-latest
       docker run -e 'ACCEPT_EULA=Y' -e 'SA_PASSWORD=$(pwd)' -p 1433:1433 -h $(host) --name=$(host) -d mcr.microsoft.com/mssql/server:2017-latest
       docker ps -a
-      sleep 5
+      sleep 10
       docker exec -t $(host) /opt/mssql-tools/bin/sqlcmd -S $(server) -U $(uid) -P $(pwd) -Q 'select @@Version'
     displayName: 'Run SQL Server for Linux'
 
diff --git a/source/pdo_sqlsrv/pdo_dbh.cpp b/source/pdo_sqlsrv/pdo_dbh.cpp
index d950ac3b..9667500e 100644
--- a/source/pdo_sqlsrv/pdo_dbh.cpp
+++ b/source/pdo_sqlsrv/pdo_dbh.cpp
@@ -489,26 +489,13 @@ struct pdo_dbh_methods pdo_sqlsrv_dbh_methods = {
 
 
 // log a function entry point
-#ifndef _WIN32
 #define PDO_LOG_DBH_ENTRY \
 { \
     pdo_sqlsrv_dbh* driver_dbh = reinterpret_cast<pdo_sqlsrv_dbh*>( dbh->driver_data ); \
-    driver_dbh->set_func( __FUNCTION__ ); \
-    int length = strlen( __FUNCTION__ ) + strlen( ": entering" ); \
-    char func[length+1]; \
-    memset(func, '\0', length+1); \
-    strcpy_s( func, sizeof( __FUNCTION__ ), __FUNCTION__ ); \
-    strcat_s( func, length+1, ": entering" ); \
-    LOG( SEV_NOTICE, func ); \
+    if (driver_dbh != NULL) driver_dbh->set_func(__FUNCTION__); \
+    core_sqlsrv_register_severity_checker(pdo_severity_check); \
+    LOG(SEV_NOTICE, "%1!s!: entering", __FUNCTION__); \
 }
-#else
-#define PDO_LOG_DBH_ENTRY \
-{ \
-    pdo_sqlsrv_dbh* driver_dbh = reinterpret_cast<pdo_sqlsrv_dbh*>( dbh->driver_data ); \
-    driver_dbh->set_func( __FUNCTION__ ); \
-    LOG( SEV_NOTICE, __FUNCTION__ ## ": entering" ); \
-}
-#endif
 
 // constructor for the internal object for connections
 pdo_sqlsrv_dbh::pdo_sqlsrv_dbh( _In_ SQLHANDLE h, _In_ error_callback e, _In_ void* driver TSRMLS_DC ) :
@@ -547,7 +534,7 @@ pdo_sqlsrv_dbh::pdo_sqlsrv_dbh( _In_ SQLHANDLE h, _In_ error_callback e, _In_ vo
 // 0 for failure, 1 for success.
 int pdo_sqlsrv_db_handle_factory( _Inout_ pdo_dbh_t *dbh, _In_opt_ zval *driver_options TSRMLS_DC) 
 {
-    LOG( SEV_NOTICE, "pdo_sqlsrv_db_handle_factory: entering" );
+    PDO_LOG_DBH_ENTRY;
 
     hash_auto_ptr pdo_conn_options_ht;
     pdo_error_mode prev_err_mode = dbh->error_mode;
diff --git a/source/pdo_sqlsrv/pdo_init.cpp b/source/pdo_sqlsrv/pdo_init.cpp
index 4f1a8845..e471561f 100644
--- a/source/pdo_sqlsrv/pdo_init.cpp
+++ b/source/pdo_sqlsrv/pdo_init.cpp
@@ -128,11 +128,11 @@ PHP_MINIT_FUNCTION(pdo_sqlsrv)
     ZEND_TSRMLS_CACHE_UPDATE();
 #endif
 
-    core_sqlsrv_register_logger( pdo_sqlsrv_log );
+    core_sqlsrv_register_severity_checker(pdo_severity_check);
 
     REGISTER_INI_ENTRIES();
     
-    LOG( SEV_NOTICE, "pdo_sqlsrv: entering minit" );
+    PDO_LOG_NOTICE("pdo_sqlsrv: entering minit");
 
     // initialize list of pdo errors
     g_pdo_errors_ht = reinterpret_cast<HashTable*>( pemalloc( sizeof( HashTable ), 1 ));
@@ -200,7 +200,7 @@ PHP_MSHUTDOWN_FUNCTION(pdo_sqlsrv)
     }
     catch( ... ) {
 
-        LOG( SEV_NOTICE, "Unknown exception caught in PHP_MSHUTDOWN_FUNCTION(pdo_sqlsrv)" );
+        PDO_LOG_NOTICE("Unknown exception caught in PHP_MSHUTDOWN_FUNCTION(pdo_sqlsrv)");
         return FAILURE;
     }
 
@@ -225,18 +225,18 @@ PHP_RINIT_FUNCTION(pdo_sqlsrv)
     int set_locale = PDO_SQLSRV_G(set_locale_info);
     if (set_locale == 2) {
         setlocale(LC_ALL, "");
-        LOG(SEV_NOTICE, "pdo_sqlsrv: setlocale LC_ALL");
+        PDO_LOG_NOTICE("pdo_sqlsrv: setlocale LC_ALL");
     }
     else if (set_locale == 1) {
         setlocale(LC_CTYPE, "");
-        LOG(SEV_NOTICE, "pdo_sqlsrv: setlocale LC_CTYPE");
+        PDO_LOG_NOTICE("pdo_sqlsrv: setlocale LC_CTYPE");
     } 
     else {
-        LOG(SEV_NOTICE, "pdo_sqlsrv: setlocale NONE");
+        PDO_LOG_NOTICE("pdo_sqlsrv: setlocale NONE");
     }
 #endif
 
-    LOG( SEV_NOTICE, "pdo_sqlsrv: entering rinit" );
+    PDO_LOG_NOTICE("pdo_sqlsrv: entering rinit");
  
     return SUCCESS;
 }
@@ -250,7 +250,7 @@ PHP_RSHUTDOWN_FUNCTION(pdo_sqlsrv)
     SQLSRV_UNUSED( module_number );
     SQLSRV_UNUSED( type );
 
-    LOG( SEV_NOTICE, "pdo_sqlsrv: entering rshutdown" );
+    PDO_LOG_NOTICE("pdo_sqlsrv: entering rshutdown");
 
     return SUCCESS;
 }
diff --git a/source/pdo_sqlsrv/pdo_stmt.cpp b/source/pdo_sqlsrv/pdo_stmt.cpp
index 65f5a7da..37afbf38 100644
--- a/source/pdo_sqlsrv/pdo_stmt.cpp
+++ b/source/pdo_sqlsrv/pdo_stmt.cpp
@@ -351,26 +351,13 @@ void stmt_option_fetch_datetime:: operator()( _Inout_ sqlsrv_stmt* stmt, stmt_op
 }
 
 // log a function entry point
-#ifndef _WIN32
 #define PDO_LOG_STMT_ENTRY \
 { \
     pdo_sqlsrv_stmt* driver_stmt = reinterpret_cast<pdo_sqlsrv_stmt*>( stmt->driver_data ); \
-    driver_stmt->set_func( __FUNCTION__ ); \
-    int length = strlen( __FUNCTION__ ) + strlen( ": entering" ); \
-    char func[length+1]; \
-    memset(func, '\0', length+1); \
-    strcpy_s( func, sizeof( __FUNCTION__ ), __FUNCTION__ ); \
-    strcat_s( func, length+1, ": entering" ); \
-    LOG( SEV_NOTICE, func ); \
+    if (driver_stmt != NULL) driver_stmt->set_func( __FUNCTION__ ); \
+    core_sqlsrv_register_severity_checker(pdo_severity_check); \
+    LOG(SEV_NOTICE, "%1!s!: entering", __FUNCTION__); \
 }
-#else
-#define PDO_LOG_STMT_ENTRY \
-{ \
-    pdo_sqlsrv_stmt* driver_stmt = reinterpret_cast<pdo_sqlsrv_stmt*>( stmt->driver_data ); \
-    driver_stmt->set_func( __FUNCTION__ ); \
-    LOG( SEV_NOTICE, __FUNCTION__ ## ": entering" ); \
-}
-#endif
 
 // PDO SQLSRV statement destructor
 pdo_sqlsrv_stmt::~pdo_sqlsrv_stmt( void )
diff --git a/source/pdo_sqlsrv/pdo_util.cpp b/source/pdo_sqlsrv/pdo_util.cpp
index 56048330..34e1a4ec 100644
--- a/source/pdo_sqlsrv/pdo_util.cpp
+++ b/source/pdo_sqlsrv/pdo_util.cpp
@@ -39,13 +39,6 @@ const int MAX_DIGITS = 11; // +-2 billion = 10 digits + 1 for the sign if negati
 // the warning message is not the error message alone; it must take WARNING_TEMPLATE above into consideration without the formats
 const int WARNING_MIN_LENGTH = static_cast<const int>( strlen( WARNING_TEMPLATE ) - strlen( "%1!s!%2!d!%3!s!" ));
 
-// buffer used to hold a formatted log message prior to actually logging it.
-const int LOG_MSG_SIZE = 2048;
-char log_msg[LOG_MSG_SIZE] = {'\0'};
-
-// internal error that says that FormatMessage failed
-SQLCHAR INTERNAL_FORMAT_ERROR[] = "An internal error occurred.  FormatMessage failed writing an error message.";
-
 // Returns a sqlsrv_error for a given error code.
 sqlsrv_error_const* get_error_message( _In_opt_ unsigned int sqlsrv_error_code);
 
@@ -623,22 +616,10 @@ void pdo_sqlsrv_retrieve_context_error( _In_ sqlsrv_error const* last_error, _Ou
     }
 }
 
-// Formats the error message and writes to the php error log.
-void pdo_sqlsrv_log( _In_opt_ unsigned int severity TSRMLS_DC, _In_opt_ const char* msg, _In_opt_ va_list* print_args )
+// check the global variable of pdo_sqlsrv severity whether the message qualifies to be logged with the LOG macro
+bool pdo_severity_check(_In_ unsigned int severity TSRMLS_DC)
 {
-    if( (severity & PDO_SQLSRV_G( log_severity )) == 0 ) {
-        return;
-    }
-
-    DWORD rc = FormatMessage( FORMAT_MESSAGE_FROM_STRING, msg, 0, 0, log_msg, LOG_MSG_SIZE, print_args );
-
-    // if an error occurs for FormatMessage, we just output an internal error occurred.
-    if( rc == 0 ) {
-        SQLSRV_STATIC_ASSERT( sizeof( INTERNAL_FORMAT_ERROR ) < sizeof( log_msg ));
-        std::copy( INTERNAL_FORMAT_ERROR, INTERNAL_FORMAT_ERROR + sizeof( INTERNAL_FORMAT_ERROR ), log_msg );
-    }
-
-    php_log_err( log_msg TSRMLS_CC );
+    return ((severity & PDO_SQLSRV_G(pdo_log_severity)));
 }
 
 namespace {
diff --git a/source/pdo_sqlsrv/php_pdo_sqlsrv.h b/source/pdo_sqlsrv/php_pdo_sqlsrv.h
index ab1aaf26..79a294f9 100644
--- a/source/pdo_sqlsrv/php_pdo_sqlsrv.h
+++ b/source/pdo_sqlsrv/php_pdo_sqlsrv.h
@@ -29,7 +29,7 @@
 // request level variables
 ZEND_BEGIN_MODULE_GLOBALS(pdo_sqlsrv)
 
-unsigned int log_severity;
+unsigned int pdo_log_severity;
 zend_long client_buffer_max_size;
 
 #ifndef _WIN32
diff --git a/source/pdo_sqlsrv/php_pdo_sqlsrv_int.h b/source/pdo_sqlsrv/php_pdo_sqlsrv_int.h
index 2934e11f..2caf1985 100644
--- a/source/pdo_sqlsrv/php_pdo_sqlsrv_int.h
+++ b/source/pdo_sqlsrv/php_pdo_sqlsrv_int.h
@@ -60,7 +60,7 @@ extern HMODULE g_sqlsrv_hmodule;
 #endif
 
 PHP_INI_BEGIN()
-    STD_PHP_INI_ENTRY( INI_PREFIX INI_PDO_SQLSRV_LOG , "0", PHP_INI_ALL, OnUpdateLong, log_severity,
+    STD_PHP_INI_ENTRY( INI_PREFIX INI_PDO_SQLSRV_LOG , "0", PHP_INI_ALL, OnUpdateLong, pdo_log_severity,
                          zend_pdo_sqlsrv_globals, pdo_sqlsrv_globals )
     STD_PHP_INI_ENTRY( INI_PREFIX INI_PDO_SQLSRV_CLIENT_BUFFER_MAX_SIZE , INI_BUFFERED_QUERY_LIMIT_DEFAULT, PHP_INI_ALL, OnUpdateLong,
                        client_buffer_max_size, zend_pdo_sqlsrv_globals, pdo_sqlsrv_globals )
@@ -326,6 +326,10 @@ inline void pdo_reset_dbh_error( _Inout_ pdo_dbh_t* dbh TSRMLS_DC )
     }
 }
 
+#define PDO_LOG_NOTICE(message) \
+   core_sqlsrv_register_severity_checker(pdo_severity_check); \
+   LOG(SEV_NOTICE, message);
+
 #define PDO_RESET_DBH_ERROR     pdo_reset_dbh_error( dbh TSRMLS_CC );
 
 inline void pdo_reset_stmt_error( _Inout_ pdo_stmt_t* stmt )
@@ -417,8 +421,8 @@ namespace pdo {
 
 } // namespace pdo
 
-// logger for pdo_sqlsrv called by the core layer when it wants to log something with the LOG macro
-void pdo_sqlsrv_log( _In_opt_ unsigned int severity TSRMLS_DC, _In_opt_ const char* msg, _In_opt_ va_list* print_args );
+// check the global variable of pdo_sqlsrv severity whether the message qualifies to be logged with the LOG macro
+bool pdo_severity_check(_In_ unsigned int severity TSRMLS_DC);
 
 
 #endif  /* PHP_PDO_SQLSRV_INT_H */
diff --git a/source/shared/core_sqlsrv.h b/source/shared/core_sqlsrv.h
index d576993d..e91b44c5 100644
--- a/source/shared/core_sqlsrv.h
+++ b/source/shared/core_sqlsrv.h
@@ -287,14 +287,12 @@ struct sqlsrv_static_assert<true> { _In_ static const int value = 1; };
 // Logging
 //*********************************************************************************************************************************
 // log_callback
-// a driver specific callback for logging messages
+// a driver specific callback for checking if the messages are qualified to be logged:
 // severity - severity of the message: notice, warning, or error
-// msg - the message to log in a FormatMessage style formatting
-// print_args - args to the message
-typedef void (*log_callback)( _In_ unsigned int severity TSRMLS_DC, _In_ const char* msg, _In_opt_ va_list* print_args );
+typedef bool (*severity_callback)(_In_ unsigned int severity TSRMLS_DC);
 
-// each driver must register a log callback.  This should be the first thing a driver does.
-void core_sqlsrv_register_logger( _In_ log_callback );
+// each driver must register a severity checker callback for logging to work according to the INI settings
+void core_sqlsrv_register_severity_checker(_In_ severity_callback driver_checker);
 
 // a simple wrapper around a PHP error logging function.
 void write_to_log( _In_ unsigned int severity TSRMLS_DC, _In_ const char* msg, ... );
diff --git a/source/shared/core_util.cpp b/source/shared/core_util.cpp
index 2853a22a..bc51b34b 100644
--- a/source/shared/core_util.cpp
+++ b/source/shared/core_util.cpp
@@ -23,10 +23,16 @@
 
 namespace {
 
+severity_callback g_driver_severity;
+
 // *** internal constants ***
-log_callback g_driver_log;
+
+// buffer used to hold a formatted log message prior to actually logging it.
+const int LOG_MSG_SIZE = 2048;
+
 // internal error that says that FormatMessage failed
 SQLCHAR INTERNAL_FORMAT_ERROR[] = "An internal error occurred.  FormatMessage failed writing an error message.";
+
 // buffer used to hold a formatted log message prior to actually logging it.
 char last_err_msg[2048] = {'\0'};  // 2k to hold the error messages
 
@@ -35,6 +41,25 @@ unsigned int convert_string_from_default_encoding( _In_ unsigned int php_encodin
                                                    _In_ unsigned int mbcs_len, 
                                                    _Out_writes_(utf16_len) __transfer( mbcs_in_string ) SQLWCHAR* utf16_out_string,
                                                    _In_ unsigned int utf16_len, bool use_strict_conversion = false );
+
+// invoked by write_to_log() when the message severity qualifies to be logged
+// msg - the message to log in a FormatMessage style formatting
+// print_args - args to the message
+void log_activity(_In_opt_ const char* msg, _In_opt_ va_list* print_args)
+{
+    char log_msg[LOG_MSG_SIZE] = { '\0' };
+
+    DWORD rc = FormatMessage(FORMAT_MESSAGE_FROM_STRING, msg, 0, 0, log_msg, LOG_MSG_SIZE, print_args);
+
+    // if an error occurs for FormatMessage, we just output an internal error occurred.
+    if (rc == 0) {
+        SQLSRV_STATIC_ASSERT(sizeof(INTERNAL_FORMAT_ERROR) < sizeof(log_msg));
+        std::copy(INTERNAL_FORMAT_ERROR, INTERNAL_FORMAT_ERROR + sizeof(INTERNAL_FORMAT_ERROR), log_msg);
+    }
+
+    php_log_err(log_msg TSRMLS_CC);
+}
+
 }
 
 // SQLSTATE for all internal errors 
@@ -47,22 +72,24 @@ SQLCHAR SSPWARN[] = "01SSP";
 // the script (sqlsrv_configure).
 void write_to_log( _In_ unsigned int severity TSRMLS_DC, _In_ const char* msg, ...)
 {
-    SQLSRV_ASSERT( !(g_driver_log == NULL), "Must register a driver log function." );
+    SQLSRV_ASSERT( !(g_driver_severity == NULL), "Must register a driver checker function." );
+    if (!g_driver_severity(severity TSRMLS_CC)) {
+        return;
+    }
 
     va_list args;
     va_start( args, msg );
 
-    g_driver_log( severity TSRMLS_CC, msg, &args );
+    log_activity(msg, &args);
 
     va_end( args );
 }
 
-void core_sqlsrv_register_logger( _In_ log_callback driver_logger )
+void core_sqlsrv_register_severity_checker(_In_ severity_callback driver_checker)
 {
-    g_driver_log = driver_logger;
+    g_driver_severity = driver_checker;
 }
 
-
 // convert a string from utf-16 to the encoding and return the new string in the pointer parameter and new
 // length in the len parameter.  If no errors occurred during convertion, true is returned and the original
 // utf-16 string is released by this function if no errors occurred.  Otherwise the parameters are not changed
diff --git a/source/sqlsrv/conn.cpp b/source/sqlsrv/conn.cpp
index c4ed6362..58aaf14b 100644
--- a/source/sqlsrv/conn.cpp
+++ b/source/sqlsrv/conn.cpp
@@ -629,10 +629,9 @@ const connection_option SS_CONN_OPTS[] = {
 
 PHP_FUNCTION ( sqlsrv_connect ) 
 {
-    
     LOG_FUNCTION( "sqlsrv_connect" );
-    SET_FUNCTION_NAME( *g_ss_henv_cp );
-    SET_FUNCTION_NAME( *g_ss_henv_ncp );
+    g_ss_henv_cp->set_func(_FN_);
+    g_ss_henv_ncp->set_func(_FN_);
 
     reset_errors( TSRMLS_C );
 
@@ -785,7 +784,7 @@ PHP_FUNCTION( sqlsrv_close )
         
         // dummy context to pass to the error handler
         error_ctx = new (sqlsrv_malloc( sizeof( sqlsrv_context ))) sqlsrv_context( 0, ss_error_handler, NULL );
-        SET_FUNCTION_NAME( *error_ctx );
+        error_ctx->set_func(_FN_);
 
         if( zend_parse_parameters(ZEND_NUM_ARGS() TSRMLS_CC, "r", &conn_r) == FAILURE ) {
         
@@ -816,7 +815,7 @@ PHP_FUNCTION( sqlsrv_close )
             throw ss::SSException();
         }   
 
-        SET_FUNCTION_NAME( *conn );
+        conn->set_func(_FN_);
         
         // cause any variables still holding a reference to this to be invalid so they cause
         // an error when passed to a sqlsrv function.  There's nothing we can do if the 
@@ -845,13 +844,15 @@ PHP_FUNCTION( sqlsrv_close )
 
 void __cdecl sqlsrv_conn_dtor( _Inout_ zend_resource *rsrc TSRMLS_DC )
 {
-    LOG_FUNCTION( "sqlsrv_conn_dtor" );
+    // Without sqlsrv_close(), this function is invoked by php during the final clean up stage. 
+    // To prevent memory/resource leaks, no more logging at this point.
+    //LOG_FUNCTION( "sqlsrv_conn_dtor" );
 
     // get the structure
     ss_sqlsrv_conn *conn = static_cast<ss_sqlsrv_conn*>( rsrc->ptr );
     SQLSRV_ASSERT( conn != NULL, "sqlsrv_conn_dtor: connection was null");
 
-    SET_FUNCTION_NAME( *conn );
+    conn->set_func(__func__);
 
     // close all statements associated with the connection.
     sqlsrv_conn_close_stmts( conn TSRMLS_CC );
diff --git a/source/sqlsrv/init.cpp b/source/sqlsrv/init.cpp
index bc069205..96f5338f 100644
--- a/source/sqlsrv/init.cpp
+++ b/source/sqlsrv/init.cpp
@@ -271,8 +271,8 @@ PHP_MINIT_FUNCTION(sqlsrv)
 {
     SQLSRV_UNUSED( type );
 
-    core_sqlsrv_register_logger( ss_sqlsrv_log );
-	
+    core_sqlsrv_register_severity_checker(ss_severity_check);
+
     // our global variables are initialized in the RINIT function
 #if defined(ZTS) 
     if( ts_allocate_id( &sqlsrv_globals_id,
diff --git a/source/sqlsrv/php_sqlsrv_int.h b/source/sqlsrv/php_sqlsrv_int.h
index 9ca59d9e..fae7082e 100644
--- a/source/sqlsrv/php_sqlsrv_int.h
+++ b/source/sqlsrv/php_sqlsrv_int.h
@@ -313,15 +313,11 @@ public:
 #define LOG_FUNCTION( function_name ) \
    const char* _FN_ = function_name; \
    SQLSRV_G( current_subsystem ) = current_log_subsystem; \
-   LOG( SEV_NOTICE, "%1!s!: entering", _FN_ ); 
+   core_sqlsrv_register_severity_checker(ss_severity_check); \
+   LOG(SEV_NOTICE, "%1!s!: entering", _FN_); 
 
-#define SET_FUNCTION_NAME( context ) \
-{ \
-    (context).set_func( _FN_ ); \
-}
-
-// logger for ss_sqlsrv called by the core layer when it wants to log something with the LOG macro
-void ss_sqlsrv_log( _In_ unsigned int severity TSRMLS_DC, _In_opt_ const char* msg, _In_opt_ va_list* print_args );
+// check the global variables of sqlsrv severity whether the message qualifies to be logged with the LOG macro
+bool ss_severity_check(_In_ unsigned int severity TSRMLS_DC);
 
 // subsystems that may report log messages.  These may be used to filter which systems write to the log to prevent noise.
 enum logging_subsystems {
diff --git a/source/sqlsrv/stmt.cpp b/source/sqlsrv/stmt.cpp
index 05d46b6c..c7f002dc 100644
--- a/source/sqlsrv/stmt.cpp
+++ b/source/sqlsrv/stmt.cpp
@@ -1371,7 +1371,6 @@ void __cdecl sqlsrv_stmt_dtor( _Inout_ zend_resource *rsrc TSRMLS_DC )
 
 PHP_FUNCTION( sqlsrv_free_stmt )
 {
-
     LOG_FUNCTION( "sqlsrv_free_stmt" );
 
     zval* stmt_r = NULL;
@@ -1384,7 +1383,7 @@ PHP_FUNCTION( sqlsrv_free_stmt )
 
         // dummy context to pass to the error handler
         error_ctx = new (sqlsrv_malloc( sizeof( sqlsrv_context ))) sqlsrv_context( 0, ss_error_handler, NULL );
-        SET_FUNCTION_NAME( *error_ctx );
+        error_ctx->set_func(_FN_);
 
         // take only the statement resource
         if( zend_parse_parameters( ZEND_NUM_ARGS() TSRMLS_CC, "r", &stmt_r ) == FAILURE ) {
diff --git a/source/sqlsrv/util.cpp b/source/sqlsrv/util.cpp
index 671f6bf4..b91f17c2 100644
--- a/source/sqlsrv/util.cpp
+++ b/source/sqlsrv/util.cpp
@@ -30,13 +30,6 @@ namespace {
 // current subsytem.  defined for the CHECK_SQL_{ERROR|WARNING} macros
 unsigned int current_log_subsystem = LOG_UTIL;
 
-// buffer used to hold a formatted log message prior to actually logging it.
-const int LOG_MSG_SIZE = 2048;
-char log_msg[LOG_MSG_SIZE] = {'\0'};
-
-// internal error that says that FormatMessage failed
-SQLCHAR INTERNAL_FORMAT_ERROR[] = "An internal error occurred.  FormatMessage failed writing an error message.";
-
 // *** internal functions ***
 sqlsrv_error_const* get_error_message( _In_ unsigned int sqlsrv_error_code );
 
@@ -457,21 +450,10 @@ ss_error SS_ERRORS[] = {
     { UINT_MAX, {} }
 };
 
-// Formats an error message and finally writes it to the php log.
-void ss_sqlsrv_log( _In_ unsigned int severity TSRMLS_DC, _In_opt_ const char* msg, _In_opt_ va_list* print_args )
+// check the global variables of sqlsrv severity whether the message qualifies to be logged with the LOG macro
+bool ss_severity_check(_In_ unsigned int severity TSRMLS_DC)
 {
-    if(( severity & SQLSRV_G( log_severity )) && ( SQLSRV_G( current_subsystem ) & SQLSRV_G( log_subsystems ))) {
-
-        DWORD rc = FormatMessage( FORMAT_MESSAGE_FROM_STRING, msg, 0, 0, log_msg, LOG_MSG_SIZE, print_args );
-    
-        // if an error occurs for FormatMessage, we just output an internal error occurred.
-        if( rc == 0 ) {
-            SQLSRV_STATIC_ASSERT( sizeof( INTERNAL_FORMAT_ERROR ) < sizeof( log_msg ));
-            std::copy( INTERNAL_FORMAT_ERROR, INTERNAL_FORMAT_ERROR + sizeof( INTERNAL_FORMAT_ERROR ), log_msg );
-        }
-
-        php_log_err( log_msg TSRMLS_CC );
-    }
+    return ((severity & SQLSRV_G(log_severity)) && (SQLSRV_G(current_subsystem) & SQLSRV_G(log_subsystems)));
 }
 
 bool ss_error_handler( _Inout_ sqlsrv_context& ctx, _In_ unsigned int sqlsrv_error_code, _In_ bool warning TSRMLS_DC, _In_opt_ va_list* print_args )
@@ -598,7 +580,7 @@ PHP_FUNCTION( sqlsrv_configure )
 
         // dummy context to pass onto the error handler
         error_ctx = new ( sqlsrv_malloc( sizeof( sqlsrv_context ))) sqlsrv_context( 0, ss_error_handler, NULL );
-        SET_FUNCTION_NAME( *error_ctx );
+        error_ctx->set_func(_FN_);
     
         int zr = zend_parse_parameters( ZEND_NUM_ARGS() TSRMLS_CC, "sz", &option, &option_len, &value_z );
         CHECK_CUSTOM_ERROR(( zr == FAILURE ), error_ctx, SS_SQLSRV_ERROR_INVALID_FUNCTION_PARAMETER, _FN_ ) {
@@ -718,7 +700,7 @@ PHP_FUNCTION( sqlsrv_get_config )
            
         // dummy context to pass onto the error handler
         error_ctx = new ( sqlsrv_malloc( sizeof( sqlsrv_context ))) sqlsrv_context( 0, ss_error_handler, NULL );
-        SET_FUNCTION_NAME( *error_ctx );
+        error_ctx->set_func(_FN_);
 
         int zr = zend_parse_parameters( ZEND_NUM_ARGS() TSRMLS_CC, "s", &option, &option_len );
         CHECK_CUSTOM_ERROR(( zr == FAILURE ), error_ctx, SS_SQLSRV_ERROR_INVALID_FUNCTION_PARAMETER, _FN_ ) {
diff --git a/test/functional/pdo_sqlsrv/pdo_connection_logs.phpt b/test/functional/pdo_sqlsrv/pdo_connection_logs.phpt
new file mode 100644
index 00000000..46ea1cdf
--- /dev/null
+++ b/test/functional/pdo_sqlsrv/pdo_connection_logs.phpt
@@ -0,0 +1,65 @@
+--TEST--
+Test simple logging with connection, simple query and then close
+--SKIPIF--
+<?php require('skipif.inc'); ?>
+--FILE--
+<?php
+require_once("MsCommon_mid-refactor.inc");
+
+function toConnect()
+{
+    require("MsSetup.inc");
+    
+    // Basic connection
+    $dsn = getDSN($server, $databaseName, $driver);
+    $conn = new PDO($dsn, $uid, $pwd);
+    $conn->setAttribute(PDO::ATTR_ERRMODE, PDO::ERRMODE_EXCEPTION);
+
+    return $conn;
+}
+
+try {
+    ini_set('log_errors', '1');
+
+    $logFilename = 'php_errors.log';
+    $logFilepath = dirname(__FILE__).'/'.$logFilename;
+    if (file_exists($logFilepath)) {
+        unlink($logFilepath);
+    }
+    
+    ini_set('error_log', $logFilepath);
+    ini_set('pdo_sqlsrv.log_severity', '-1');
+
+    $conn = toConnect();
+    $stmt = $conn->query("SELECT @@Version");
+    
+    // Ignore the fetch results
+    $stmt->fetchAll();
+    
+    unset($conn);
+
+    if (file_exists($logFilepath)) {
+        echo file_get_contents($logFilepath);
+        unlink($logFilepath);
+    } else {
+        echo "$logFilepath is missing!\n";
+    }
+
+    echo "Done\n";
+} catch (Exception $e) {
+    var_dump($e);
+}
+
+?>
+--EXPECTF--
+[%s UTC] pdo_sqlsrv_db_handle_factory: entering
+[%s UTC] pdo_sqlsrv_db_handle_factory: SQLSTATE = 01000
+[%s UTC] pdo_sqlsrv_db_handle_factory: error code = 5701
+[%s UTC] pdo_sqlsrv_db_handle_factory: message = %s[SQL Server]Changed database context to '%s'.
+[%s UTC] pdo_sqlsrv_dbh_prepare: entering
+[%s UTC] pdo_sqlsrv_stmt_execute: entering
+[%s UTC] pdo_sqlsrv_stmt_describe_col: entering
+[%s UTC] pdo_sqlsrv_stmt_fetch: entering
+[%s UTC] pdo_sqlsrv_stmt_get_col_data: entering
+[%s UTC] pdo_sqlsrv_stmt_fetch: entering
+Done
\ No newline at end of file
diff --git a/test/functional/pdo_sqlsrv/pdo_errorMode_logs.phpt b/test/functional/pdo_sqlsrv/pdo_errorMode_logs.phpt
new file mode 100644
index 00000000..a0169696
--- /dev/null
+++ b/test/functional/pdo_sqlsrv/pdo_errorMode_logs.phpt
@@ -0,0 +1,116 @@
+--TEST--
+Test different error modes. The queries will try to do a select on a non-existing table
+--DESCRIPTION--
+This is similar to pdo_errorMode.phpt but will display the contents of php 
+error logs based on log severity.
+--SKIPIF--
+<?php require('skipif_mid-refactor.inc'); ?>
+--FILE--
+<?php
+require_once("MsCommon_mid-refactor.inc");
+
+function toConnect()
+{
+    require("MsSetup.inc");
+    
+    $dsn = getDSN($server, $databaseName, $driver);
+    $conn = new PDO($dsn, $uid, $pwd);
+    return $conn;
+}
+
+function testException($conn)
+{
+    $conn->setAttribute(PDO::ATTR_ERRMODE, PDO::ERRMODE_EXCEPTION);
+
+    global $sql;
+    try {
+        $q = $conn->query($sql);
+    } catch (Exception $e) {
+        // do nothing
+    }
+}
+
+function testWarning($conn)
+{
+    // This forces PHP to log errors rather than displaying errors 
+    // on screen -- only required for PDO::ERRMODE_WARNING
+    ini_set('display_errors', '0');
+    $conn->setAttribute(PDO::ATTR_ERRMODE, PDO::ERRMODE_WARNING);
+
+    global $sql;
+    $q = $conn->query($sql);
+}
+
+function runtests($severity)
+{
+    global $conn;
+    
+    $logFilename = 'php_errors' . $severity . '.log';
+    $logFilepath = dirname(__FILE__).'/'.$logFilename;
+    if (file_exists($logFilepath)) {
+        unlink($logFilepath);
+    }
+
+    ini_set('error_log', $logFilepath);
+    ini_set('pdo_sqlsrv.log_severity', $severity);
+
+    if ($severity === '2' ) {
+        testWarning($conn);
+    } else {
+        testException($conn);
+    }
+
+    if (file_exists($logFilepath)) {
+        if ($severity == '0') {
+            echo "$logFilepath should not exist\n";
+        }
+        echo file_get_contents($logFilepath);
+        unlink($logFilepath);
+    }
+    
+    // Now reset logging by disabling it
+    ini_set('pdo_sqlsrv.log_severity', '0');
+    echo "Done with $severity\n\n";
+}
+
+try {
+    ini_set('log_errors', '1');
+    ini_set('pdo_sqlsrv.log_severity', '0');
+
+    $conn = toConnect();
+    $sql = "SELECT * FROM temp_table";
+
+    runtests('0');
+    runtests('1');
+    runtests('2');
+    runtests('4');
+    runtests('-1');
+} catch (Exception $e) {
+    var_dump($e);
+}
+
+?>
+--EXPECTF--
+Done with 0
+
+[%s UTC] pdo_sqlsrv_stmt_execute: SQLSTATE = 42S02
+[%s UTC] pdo_sqlsrv_stmt_execute: error code = 208
+[%s UTC] pdo_sqlsrv_stmt_execute: message = %s[SQL Server]Invalid object name 'temp_table'.
+Done with 1
+
+[%s UTC] PHP Warning:  PDO::query(): SQLSTATE[42S02]: Base table or view not found: 208 %s[SQL Server]Invalid object name 'temp_table'. in %spdo_errorMode_logs.php on line %d
+Done with 2
+
+[%s UTC] pdo_sqlsrv_stmt_dtor: entering
+[%s UTC] pdo_sqlsrv_dbh_prepare: entering
+[%s UTC] pdo_sqlsrv_stmt_execute: entering
+Done with 4
+
+[%s UTC] pdo_sqlsrv_stmt_dtor: entering
+[%s UTC] pdo_sqlsrv_dbh_prepare: entering
+[%s UTC] pdo_sqlsrv_stmt_execute: entering
+[%s UTC] pdo_sqlsrv_stmt_execute: SQLSTATE = 42S02
+[%s UTC] pdo_sqlsrv_stmt_execute: error code = 208
+[%s UTC] pdo_sqlsrv_stmt_execute: message = %s[SQL Server]Invalid object name 'temp_table'.
+Done with -1
+
diff --git a/test/functional/sqlsrv/sqlsrv_commit_logs.phpt b/test/functional/sqlsrv/sqlsrv_commit_logs.phpt
new file mode 100644
index 00000000..ba17483e
--- /dev/null
+++ b/test/functional/sqlsrv/sqlsrv_commit_logs.phpt
@@ -0,0 +1,63 @@
+--TEST--
+Test sqlsrv_commit method with logging
+--DESCRIPTION--
+Similar to sqlsrv_commit.phpt but also test some basic logging activities
+By adding integer values together, we can specify more than one logging option at a time.
+SQLSRV_LOG_SYSTEM_CONN (2) Turns on logging of connection activity.
+SQLSRV_LOG_SYSTEM_STMT (4) Turns on logging of statement activity.
+
+For example, sqlsrv.LogSubsystems = 6
+turns on logging of connection and statement activities
+--SKIPIF--
+<?php require_once('skipif.inc'); ?>
+--FILE--
+<?php
+    sqlsrv_configure('LogSeverity', SQLSRV_LOG_SEVERITY_NOTICE);
+    sqlsrv_configure('LogSubsystems', 6);
+
+    require_once('MsCommon.inc');
+
+    $conn = connect();
+    if (!$conn) {
+        fatalError("Could not connect");
+    }
+
+    $stmt1 = sqlsrv_query($conn, "IF OBJECT_ID('Products', 'U') IS NOT NULL DROP TABLE Products");
+    $stmt1 = sqlsrv_query($conn, "CREATE TABLE Products (ProductID int PRIMARY KEY, ProductName nvarchar(40), CategoryID int, UnitPrice money)");
+    if ($stmt1 === false) {
+        die(print_r(sqlsrv_errors(), true));
+    }
+    sqlsrv_free_stmt($stmt1);
+
+    $stmt2 = sqlsrv_query($conn, "INSERT INTO Products (ProductID, ProductName, CategoryID, UnitPrice) VALUES (1, 'TestProduct2', 2, '13.55')");
+    $stmt3 = sqlsrv_query($conn, "SELECT * FROM Products WHERE CategoryID = 2");
+
+    if ($stmt2 && $stmt3) {
+        sqlsrv_commit($conn);
+    }
+
+    $stmt1 = sqlsrv_query($conn, "DROP TABLE Products");
+    sqlsrv_free_stmt($stmt1);
+    sqlsrv_free_stmt($stmt2);
+    sqlsrv_free_stmt($stmt3);
+
+    sqlsrv_close($conn);
+?>
+--EXPECT--
+sqlsrv_connect: entering
+sqlsrv_query: entering
+sqlsrv_query: entering
+sqlsrv_stmt_dtor: entering
+sqlsrv_free_stmt: entering
+sqlsrv_stmt_dtor: entering
+sqlsrv_query: entering
+sqlsrv_query: entering
+sqlsrv_commit: entering
+sqlsrv_query: entering
+sqlsrv_free_stmt: entering
+sqlsrv_stmt_dtor: entering
+sqlsrv_free_stmt: entering
+sqlsrv_stmt_dtor: entering
+sqlsrv_free_stmt: entering
+sqlsrv_stmt_dtor: entering
+sqlsrv_close: entering
diff --git a/test/functional/sqlsrv/sqlsrv_connect.phpt b/test/functional/sqlsrv/sqlsrv_connect.phpt
index 083e74fa..2dcacb7d 100644
--- a/test/functional/sqlsrv/sqlsrv_connect.phpt
+++ b/test/functional/sqlsrv/sqlsrv_connect.phpt
@@ -14,7 +14,7 @@ functions return FALSE for errors.
         fatalError("sqlsrv_connect should have returned false.");
     }
 
-    $conn = sqlsrv_connect("_!@#$", array( "Driver" => "Danica Patrick" ));
+    $conn = sqlsrv_connect("_!@#$", array( "Driver" => "Wrong Driver" ));
     if ($conn !== false) {
         fatalError("sqlsrv_connect should have returned false.");
     }
diff --git a/test/functional/sqlsrv/sqlsrv_connect_log_to_file.phpt b/test/functional/sqlsrv/sqlsrv_connect_log_to_file.phpt
new file mode 100644
index 00000000..4422294f
--- /dev/null
+++ b/test/functional/sqlsrv/sqlsrv_connect_log_to_file.phpt
@@ -0,0 +1,56 @@
+--TEST--
+Test functions return FALSE for errors with logging
+--DESCRIPTION--
+Similar to sqlsrv_connect_logs.phpt but this time test logging to a log file
+--SKIPIF--
+<?php require('skipif.inc'); ?>
+--FILE--
+<?php
+    require_once('MsSetup.inc');
+
+    $logFilename = 'php_errors.log';
+    $logFilepath = dirname(__FILE__).'/'.$logFilename;
+    if (file_exists($logFilepath)) {
+        unlink($logFilepath);
+    }
+
+    ini_set('log_errors', '1');
+    ini_set('error_log', $logFilepath);
+    ini_set("sqlsrv.LogSeverity", SQLSRV_LOG_SEVERITY_ALL);
+    ini_set("sqlsrv.LogSubsystems", SQLSRV_LOG_SYSTEM_ALL);
+
+    $conn = sqlsrv_connect($server, array( "Driver" => "Wrong Driver" ));
+    if ($conn !== false) {
+        fatalError("sqlsrv_connect should have returned false.");
+    }
+
+    ini_set("sqlsrv.LogSeverity", SQLSRV_LOG_SEVERITY_NOTICE);
+    $conn = sqlsrv_connect($server, array( "uid" => $uid , "pwd" => $pwd ));
+
+    if ($conn === false) {
+        fatalError("sqlsrv_connect should have connected.");
+    }
+
+    ini_set("sqlsrv.LogSeverity", SQLSRV_LOG_SEVERITY_ERROR);
+    $stmt = sqlsrv_query($conn, "SELECT * FROM some_bogus_table");
+    if ($stmt !== false) {
+        fatalError("sqlsrv_query should have returned false.");
+    }
+
+    ini_set("sqlsrv.LogSeverity", SQLSRV_LOG_SEVERITY_ALL);
+    if (file_exists($logFilepath)) {
+        echo file_get_contents($logFilepath);
+        unlink($logFilepath);
+    }
+    
+    sqlsrv_close($conn);
+?>
+--EXPECTF--
+[%s UTC] sqlsrv_connect: entering
+[%s UTC] sqlsrv_connect: SQLSTATE = IMSSP
+[%s UTC] sqlsrv_connect: error code = -106
+[%s UTC] sqlsrv_connect: message = Invalid value Wrong Driver was specified for Driver option.
+[%s UTC] sqlsrv_connect: entering
+[%s UTC] sqlsrv_query: SQLSTATE = 42S02
+[%s UTC] sqlsrv_query: error code = 208
+[%s UTC] sqlsrv_query: message = %s[SQL Server]Invalid object name 'some_bogus_table'.
\ No newline at end of file
diff --git a/test/functional/sqlsrv/sqlsrv_connect_logs.phpt b/test/functional/sqlsrv/sqlsrv_connect_logs.phpt
new file mode 100644
index 00000000..1ba654bd
--- /dev/null
+++ b/test/functional/sqlsrv/sqlsrv_connect_logs.phpt
@@ -0,0 +1,49 @@
+--TEST--
+Test functions return FALSE for errors with logging
+--DESCRIPTION--
+Similar to sqlsrv_connect.phpt but also test different settings of logging activities
+--SKIPIF--
+<?php require('skipif.inc'); ?>
+--FILE--
+<?php
+    sqlsrv_configure('WarningsReturnAsErrors', 0);
+    sqlsrv_configure('LogSeverity', SQLSRV_LOG_SEVERITY_ALL);
+    sqlsrv_configure('LogSubsystems', SQLSRV_LOG_SYSTEM_ALL);
+
+    require_once('MsSetup.inc');
+
+    $conn = sqlsrv_connect($server, array( "Driver" => "Wrong Driver" ));
+    if ($conn !== false) {
+        fatalError("sqlsrv_connect should have returned false.");
+    }
+
+    sqlsrv_configure('LogSeverity', SQLSRV_LOG_SEVERITY_NOTICE);
+    $conn = sqlsrv_connect($server, array( "uid" => $uid , "pwd" => $pwd ));
+
+    if ($conn === false) {
+        fatalError("sqlsrv_connect should have connected.");
+    }
+
+    sqlsrv_configure('LogSeverity', SQLSRV_LOG_SEVERITY_ERROR);
+    $stmt = sqlsrv_query($conn, "SELECT * FROM some_bogus_table");
+    if ($stmt !== false) {
+        fatalError("sqlsrv_query should have returned false.");
+    }
+
+    sqlsrv_configure('LogSeverity', SQLSRV_LOG_SEVERITY_WARNING);
+    
+    sqlsrv_close($conn);
+?>
+--EXPECTF--
+sqlsrv.LogSubsystems = -1
+sqlsrv_connect: entering
+sqlsrv_connect: SQLSTATE = IMSSP
+sqlsrv_connect: error code = -106
+sqlsrv_connect: message = Invalid value Wrong Driver was specified for Driver option.
+sqlsrv_configure: entering
+sqlsrv.LogSeverity = 4
+sqlsrv_connect: entering
+sqlsrv_configure: entering
+sqlsrv_query: SQLSTATE = 42S02
+sqlsrv_query: error code = 208
+sqlsrv_query: message = %s[SQL Server]Invalid object name 'some_bogus_table'.