Re: bzr commit into mysql-5.1-bugteam branch (Dao-Gang.Qu:3192) Bug#42851

[Davi Arnaut]

Hi Dao-Gang,

A few comments below.

On 11/23/09 6:42 AM, Dao-Gang.Qu@stripped wrote:
> #At file:///home/daogangqu/mysql/bzrwork/bug42851/mysql-5.1-bugteam/ based on
> revid:davi.arnaut@stripped
>
>   3192 Dao-Gang.Qu@stripped	2009-11-23
>        Bug #42851  	Spurious "Statement is not safe to log in statement format."
> warnings
>
>        Warnings in error log make error log grow too large.
>
>        The problem can be resolved by limiting the rate of messages that are
>        written to the log. A volume of messages that is less than or equal to
>        the specified rate is written to the log, whereas the volume of messages
>        that exceeds the rate is discarded.
>
>        For example,
>
>        log-warnings-ratelimit-interval = 10
>        log-warnings-ratelimit-burst = 5
>
>        This allows 5 log messages per 10 seconds. The sixth (and posterior)
>        attempts to write a log message within a 10 seconds interval are
>        discarded.

[..]

> +
> +void Log_to_file_event_handler::rate_limit_exceeded()
> +{
> +  sql_print_error("log-warnings-ratelimit-burst parameter's value (N) \
> +exceeded; discarding the rest of error messages");

Please, break the string in a way that preserves indentation:

sql_print_errror("log-warnings-ratelimit-burst parameter's value (N) "
                  "exceeded; discarding the rest of error messages");

and the message looks like broken english. What is N? Please, consult 
the documentation team if you think the original messages weren't clear 
enough -- which i think were good enough, if a user does not understand 
it, he should look it up in the docs where he/she will find a extended 
explanation.

> +}
> +
> +void Log_to_file_event_handler::rate_limit_reset(unsigned int suppressed)
> +{
> +  sql_print_error("Rate limit lifted, %u warning messages were suppressed.",
> +                  suppressed);
>   }
>
>   void Log_to_file_event_handler::init_pthread_objects()
>
> === modified file 'sql/log.h'
> --- a/sql/log.h	2009-06-18 13:52:46 +0000
> +++ b/sql/log.h	2009-11-23 08:42:40 +0000
> @@ -16,6 +16,9 @@
>   #ifndef LOG_H
>   #define LOG_H
>
> +extern ulong log_warnings_ratelimit_interval;
> +extern ulong log_warnings_ratelimit_burst;
> +
>   class Relay_log_info;
>
>   class Format_description_log_event;
> @@ -459,15 +462,88 @@ public:
>   };
>
>
> +/**
> +  Rate limiter.
> +*/
> +
> +class Rate_limit
> +{
> +  public:
> +    Rate_limit() : m_count(0), m_suppressed(0), m_begin(0),
> +                   interval(0), burst(0)
> +    {}

Please add a virtual destructor.