<div dir="ltr"><br><br><div class="gmail_quote"><div dir="ltr">On Thu, Dec 6, 2018 at 5:40 AM Tatsuo Ishii <<a href="mailto:ishii@sraoss.co.jp">ishii@sraoss.co.jp</a>> wrote:<br></div><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">> Hi<br>
> <br>
> Currently Pgpool-II spawns the num_init_children number of child processes<br>
> at the time of startup. This is the standard approach we follow in<br>
> Pgpool-II since its inception. But this approach is not very optimal for<br>
> the setups with variable load requirements. For example for the setups<br>
> where we get instantaneous load spikes let say only for small amount of<br>
> time, we still have to set the num_init_children in Pgpool-II to the<br>
> maximum value, and most of the time the majority of the the child processes<br>
> would be sitting idle and consuming the system resources.<br>
> Like consider a case of some sports website which gets huge number of user<br>
> when some sport event is happening, but for rest of the time it gets very<br>
> few visitors. But with the current available options when designing the<br>
> system using the Pgpool-II we have to set the num_init_children to the<br>
> value what we expect to get at the maximum peak time and that number of<br>
> children will be spawned by Pgpool-II at startup, which is a waste of<br>
> resources.<br>
> So my proposal is that instead of spawning all the num_init_children number<br>
> of child process at startup, we scale up and scale down the number of child<br>
> processes as per the demand. And only keep may be 10 percent of extra idle<br>
> child processes at any time.<br>
> I believe this approach will improve the load management and performance of<br>
> Pgpool-II<br>
> <br>
> What are your thought and suggestions on this.<br>
<br>
Do you have a performance measurement on this?<br></blockquote><div><br></div><div>I am running some tests to gauge the actual performance impact we get because of extra idle child process, </div><div>I will share the results on this thread.</div><div> </div><div>Thanks</div><div>Best Regards</div><div>Muhammad Usama</div><div><br></div><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">
<br>
Best regards,<br>
--<br>
Tatsuo Ishii<br>
SRA OSS, Inc. Japan<br>
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