Re: [PATCH] lock_timeout and common SIGALRM framework

2012-04-04 16:22 keltezéssel, Boszormenyi Zoltan írta:
> 2012-04-04 15:17 keltezéssel, Boszormenyi Zoltan írta:
>> Hi,
>>
>> 2012-04-04 12:30 keltezéssel, Boszormenyi Zoltan írta:
>>> Hi,
>>>
>>> attached is a patch to implement a framework to simplify and
>>> correctly nest multiplexing more than two timeout sources
>>> into the same SIGALRM signal handler.
>>>
>>> The framework is using a new internal API for timeouts:
>>>
>>> bool enable_timeout(TimeoutName tn, int delayms);
>>> bool disable_timeout(TimeoutName tn, bool keep_indicator);
>>> bool disable_all_timeouts(bool keep_indicators);
>>>
>>> A timeout source has these features to allow different initialization,
>>> cleanup and check functions and rescheduling:
>>>
>>> typedef void (*timeout_init)(TimestampTz, TimestampTz);
>>> typedef void (*timeout_destroy)(bool);
>>> typedef bool (*timeout_check)(void);
>>> typedef TimestampTz (*timeout_start)(void);
>>>
>>> typedef struct {
>>>         TimeoutName     index;
>>>         bool            resched_next;
>>>         timeout_init    timeout_init;
>>>         timeout_destroy timeout_destroy;
>>>         timeout_check   timeout_check;
>>>         timeout_start   timeout_start;
>>>         TimestampTz     fin_time;
>>> } timeout_params;
>>>
>>> This makes it possible to differentiate between the standby and
>>> statement timeouts, regular deadlock and standby deadlock using
>>> the same signal handler function.
>>>
>>> And finally, this makes it possible to implement the lock_timeout
>>> feature that we at Cybertec implemented more than 2 years ago.
>>>
>>> The patch also adds two new tests into prepared_xacts.sql to trigger
>>> the lock_timeout instead of statement_timeout.
>>>
>>> Documentation and extensive comments are included.
>>
>> Second version. Every timeout-related functions are now in a separate
>> source file, src/backend/storage/timeout.c with accessor functions.
>> There are no related global variables anymore, only the GUCs.
>
> 3rd and (for now) final version.

I lied. This is the final one. I fixed a typo in the documentation
and replaced timeout_start_time (previously static to proc.c)
with get_timeout_start(DEADLOCK_TIMEOUT). This one should
have happened in the second version.

> Tidied comments, the time checks in
> Check*() functions and function order in timeout.c.
>
>>
>>>
>>> Best regards,
>>> Zoltán Böszörményi
>>
>>
>>
>>
>
>
> -- 
> ----------------------------------
> Zoltán Böszörményi
> Cybertec Schönig&  Schönig GmbH
> Gröhrmühlgasse 26
> A-2700 Wiener Neustadt, Austria
> Web:http://www.postgresql-support.de
>       http://www.postgresql.at/
>
>


-- 
----------------------------------
Zoltán Böszörményi
Cybertec Schönig&  Schönig GmbH
Gröhrmühlgasse 26
A-2700 Wiener Neustadt, Austria
Web: http://www.postgresql-support.de
      http://www.postgresql.at/