问题描述
现象
5.6 和 5.7 时区设置相同,select now()也显示当前时间
5.7 error log 中时间和当前时间差8小时
问题分析
5.6 写 error log 函数如下
取时间的函数是localtime_r(&skr, &tm_tmp)
日志中时间和系统时区相同
static void print_buffer_to_file(enum loglevel level, const char *buffer,
size_t length)
{
time_t skr;
struct tm tm_tmp;
struct tm *start;
DBUG_ENTER("print_buffer_to_file");
DBUG_PRINT("enter",("buffer: %s", buffer));
mysql_mutex_lock(&LOCK_error_log);
skr= my_time(0);
localtime_r(&skr, &tm_tmp);
start=&tm_tmp;
fprintf(stderr, "%d-%02d-%02d %02d:%02d:%02d %lu [%s] %.*s\n",
start->tm_year + 1900,
start->tm_mon + 1,
start->tm_mday,
start->tm_hour,
start->tm_min,
start->tm_sec,
current_pid,
(level == ERROR_LEVEL ? "ERROR" : level == WARNING_LEVEL ?
"Warning" : "Note"),
(int) length, buffer);
fflush(stderr);
mysql_mutex_unlock(&LOCK_error_log);
DBUG_VOID_RETURN;
}
5.7 写 error log 函数如下
取时间的函数是 make_iso8601_timestamp(my_timestamp)
static void print_buffer_to_file(enum loglevel level, const char *buffer,
size_t length)
{
DBUG_ENTER("print_buffer_to_file");
DBUG_PRINT("enter",("buffer: %s", buffer));
char my_timestamp[iso8601_size];
my_thread_id thread_id= 0;
/*
If the thread system is up and running and we're in a connection,
add the connection ID to the log-line, otherwise 0.
*/
if (THR_THD_initialized && (current_thd != NULL))
thread_id= current_thd->thread_id();
make_iso8601_timestamp(my_timestamp);
/*
This must work even if the mutex has not been initialized yet.
At that point we should still be single threaded so that it is
safe to write without mutex.
*/
if (error_log_initialized)
mysql_mutex_lock(&LOCK_error_log);
if (error_log_buffering)
{
// Logfile not open yet, buffer messages for now.
if (buffered_messages == NULL)
buffered_messages= new (std::nothrow) std::string();
std::ostringstream s;
s << my_timestamp << " " << thread_id;
if (level == ERROR_LEVEL)
s << " [ERROR] ";
else if (level == WARNING_LEVEL)
s << " [Warning] ";
else
s << " [Note] ";
s << buffer << std::endl;
buffered_messages->append(s.str());
}
else
{
fprintf(stderr, "%s %u [%s] %.*s\n",
my_timestamp,
thread_id,
(level == ERROR_LEVEL ? "ERROR" : level == WARNING_LEVEL ?
"Warning" : "Note"),
(int) length, buffer);
fflush(stderr);
}
if (error_log_initialized)
mysql_mutex_unlock(&LOCK_error_log);
DBUG_VOID_RETURN;
}
make_iso8601_timestamp 中有代码段如下
参数 opt_log_timestamps 控制时间
if (opt_log_timestamps == 0)
gmtime_r(&seconds, &my_tm);
else
{
localtime_r(&seconds, &my_tm);
opt_log_timestamps 对应 sys_vars.cc 中的 log_timestamps
取值 const char *timestamp_type_names[]= {“UTC”, “SYSTEM”, NullS};
log_timestamps = 0 时,日志中是 UTC 时区
log_timestamps = 1 时,日志中是 SYSTEM 时区
5.7 默认 log_timestamps = 0
5.7 error log 使用系统时区
set global log_timestamps = 1;
时间: 2024-11-16 16:47:15