<div dir="ltr"><br><div class="gmail_extra"><br><div class="gmail_quote">On Tue, Apr 25, 2017 at 7:24 PM, Tatsuo Ishii <span dir="ltr"><<a href="mailto:ishii@sraoss.co.jp" target="_blank">ishii@sraoss.co.jp</a>></span> wrote:<br><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left-width:1px;border-left-style:solid;border-left-color:rgb(204,204,204);padding-left:1ex">Hi Usama,<br>
<span class="gmail-"><br>
> Hi Ishii-San<br>
><br>
> I am working on config framework modification to allow same name parameters<br>
> with and without index postfix, I am almost done with the framework related<br>
> changes.<br>
<br>
</span>Thanks!<br>
<span class="gmail-"><br>
> And now for testing I need to add one such parameter and I was thinking<br>
> instead of using a dummy configuration variable for testing I would rather<br>
</span>> add the *health_check_period* and *health_check_period[idx]* so that you<br>
<span class="gmail-">> can also use it.<br>
> For that can you tell me where do you want to create health_check_period<br>
> variable for each backend? Is BackendInfo structure is the right place?<br>
<br>
</span>I'm working on it for the part. I will push it tomorrow. BTW, unlike<br>
BackendInfo, the structure does not need to live on the shared memory.<br></blockquote><div><br></div><div>Sure thanks, And yes you are right the health_check_period doesn't needs to go in shared memory,</div><div><br></div><div>You can just push the structure related changes for the health_check_period parameters and I will make it configurable, that way it will save you the time and also I will be able to test the changes before pushing the changes.</div><div><br></div><div>Thanks</div><div>Best Regards</div><div>Muhammad Usama</div><div><br></div><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left-width:1px;border-left-style:solid;border-left-color:rgb(204,204,204);padding-left:1ex">
<div class="gmail-HOEnZb"><div class="gmail-h5"><br>
Best regards,<br>
--<br>
Tatsuo Ishii<br>
SRA OSS, Inc. Japan<br>
English: <a href="http://www.sraoss.co.jp/index_en.php" rel="noreferrer" target="_blank">http://www.sraoss.co.jp/index_<wbr>en.php</a><br>
Japanese:<a href="http://www.sraoss.co.jp" rel="noreferrer" target="_blank">http://www.sraoss.co.<wbr>jp</a><br>
<br>
> Thanks<br>
> Best Regards<br>
><br>
><br>
> On Mon, Apr 24, 2017 at 7:42 AM, Tatsuo Ishii <<a href="mailto:ishii@sraoss.co.jp">ishii@sraoss.co.jp</a>> wrote:<br>
><br>
>> >> On 21-Apr-2017, at 4:31 AM, Tatsuo Ishii <<a href="mailto:ishii@sraoss.co.jp">ishii@sraoss.co.jp</a>> wrote:<br>
>> >><br>
>> >> Usama,<br>
>> >><br>
>> >> Is it possible to have following config parameter at the same time?<br>
>> >> My feeling is we can't because current implementation of config<br>
>> >> handling does not allow it.<br>
>> >><br>
>> >> health_check_period = 10<br>
>> >> health_check_period0 = 5<br>
>> ><br>
>> > Yes, having the same named configuration parameter with and without<br>
>> index postfix would cause problem with the current implementations, but if<br>
>> we want to support this I can tweak the configuration framework to allow<br>
>> that.<br>
>><br>
>> That would be desirable.<br>
>><br>
>> Best regards,<br>
>> --<br>
>> Tatsuo Ishii<br>
>> SRA OSS, Inc. Japan<br>
>> English: <a href="http://www.sraoss.co.jp/index_en.php" rel="noreferrer" target="_blank">http://www.sraoss.co.jp/index_<wbr>en.php</a><br>
>> Japanese:<a href="http://www.sraoss.co.jp" rel="noreferrer" target="_blank">http://www.sraoss.co.<wbr>jp</a><br>
>><br>
>> > Thanks<br>
>> > Best regards<br>
>> > Muhammad Usama<br>
>> ><br>
>> >><br>
>> >> Best regards,<br>
>> >> --<br>
>> >> Tatsuo Ishii<br>
>> >> SRA OSS, Inc. Japan<br>
>> >> English: <a href="http://www.sraoss.co.jp/index_en.php" rel="noreferrer" target="_blank">http://www.sraoss.co.jp/index_<wbr>en.php</a><br>
>> >> Japanese:<a href="http://www.sraoss.co.jp" rel="noreferrer" target="_blank">http://www.sraoss.co.<wbr>jp</a><br>
>> >><br>
>> >>> Hi,<br>
>> >>><br>
>> >>> This is a Request for Comments on the new implementation of health<br>
>> >>> check aiming for Pgpool-II 3.7.<br>
>> >>><br>
>> >>> Problems:<br>
>> >>><br>
>> >>> Current implementation of health check is a single serial processing<br>
>> >>> for all of database nodes. This implies some limitations for health<br>
>> >>> check process: 1) it is not possible to specify different health check<br>
>> >>> configuration values for each database node, 2) node failure detection<br>
>> >>> may take longer. For example, if it takes 10 seconds before detecting<br>
>> >>> node 0 failure, then detecting node 1 failure will be delayed at least<br>
>> >>> 10 seconds because it starts node failure detection after node 0.<br>
>> >>><br>
>> >>> The solution:<br>
>> >>><br>
>> >>> Allow to specify health check parameters for each node. Pgpool.conf<br>
>> >>> will look like:<br>
>> >>><br>
>> >>> health_check_period0 = 10<br>
>> >>> health_check_timeout0 = 20<br>
>> >>> :<br>
>> >>> :<br>
>> >>><br>
>> >>> where "0" means database node 0 (similar concept as "backend_*0<br>
>> >>> parameters).<br>
>> >>><br>
>> >>> To make admin's life easier, current parameters can be used as<br>
>> >>> well. Suppose there are 3 nodes, and we have:<br>
>> >>><br>
>> >>> health_check_period = 10<br>
>> >>> health_check_period0 = 5<br>
>> >>><br>
>> >>> then health_check_period for node 1 and 2 will be 10, while<br>
>> >>> health_check_period for node 0 will be 5. So parameter names without<br>
>> >>> node id works as a "global variable".<br>
>> >>><br>
>> >>> The implementation:<br>
>> >>><br>
>> >>> Create separate child process of pgpool main process and let do the<br>
>> >>> heal check job for each database node. Once the health check child<br>
>> >>> process detects node failure, it signals to main process and main<br>
>> >>> process will perform failover.<br>
>> >>><br>
>> >>> This architecture makes pgpool main process simpler and robust, while<br>
>> >>> earlier detection of node failure by the health check child process.<br>
>> >>><br>
>> >>> Comments and suggestions are welcome.<br>
>> >>><br>
>> >>> Best regards,<br>
>> >>> --<br>
>> >>> Tatsuo Ishii<br>
>> >>> SRA OSS, Inc. Japan<br>
>> >>> English: <a href="http://www.sraoss.co.jp/index_en.php" rel="noreferrer" target="_blank">http://www.sraoss.co.jp/index_<wbr>en.php</a><br>
>> >>> Japanese:<a href="http://www.sraoss.co.jp" rel="noreferrer" target="_blank">http://www.sraoss.co.<wbr>jp</a><br>
>> >>> ______________________________<wbr>_________________<br>
>> >>> pgpool-hackers mailing list<br>
>> >>> <a href="mailto:pgpool-hackers@pgpool.net">pgpool-hackers@pgpool.net</a><br>
>> >>> <a href="http://www.pgpool.net/mailman/listinfo/pgpool-hackers" rel="noreferrer" target="_blank">http://www.pgpool.net/mailman/<wbr>listinfo/pgpool-hackers</a><br>
>><br>
</div></div></blockquote></div><br></div></div>