Apple Replaces Problematic 'Discoveryd' Process With mDNSresponder in 10.10.4 Beta 4

[MacRumors]

In today's fourth OS X 10.10.4 beta, Apple made a significant behind-the-scenes change that could result in improved networking performance for some users -- the removal of the "discoveryd" process. As noted by MacRumors forum members and 9to5Mac, in OS X 10.10.4 beta 4, the discoveryd process has been replaced by mDNSresponder.

Since OS X Yosemite debuted in October, there have been ongoing complaints about discoveryd consuming CPU resources, draining battery life, and causing issues with Wi-Fi. These problems have lingered for several months, even after multiple bug fixes and performance improvements included in OS X 10.10.1, 10.10.2, and 10.10.3.

Discoveryd was introduced with OS X Yosemite, replacing mDNSResponder for managing Mac networking tasks, but it's led to a host of problems like those listed above along with issues like slow wake from sleep, failures to resolve DNS names, duplicate machine names, and more, as detailed in a post earlier this year by Ars Technica. Several developers have also complained about discoveryd in Yosemite, including Instapaper's Marco Arment and Iconfactory's Craig Hockenberry.

It's no secret in the tech community that discoveryd is the root cause of so many problems. There are even crazy workarounds. With so many issues, you'd expect some information from Apple explaining ways to mitigate the problems.

The removal of the unstable discoveryd process in OS X 10.10.4 beta 4 may improve network stability problems for many users who have been experiencing continual issues. With the removal of discoveryd, Apple has reverted back to using the earlier mDNSresponder process that was used before discoveryd was implemented with OS X Yosemite.

Article Link: Apple Replaces Problematic 'Discoveryd' Process With mDNSresponder in 10.10.4 Beta 4

 

[charlien]

Thank you. I may install the beta just for this.

 

[Alisamix]

Back to the roots.
Happy to see Apple scrapping discoveryd and rehauling the whole thing.

 

[GLS]

YES.

Although I must state, configuring IPV6 to Local-Link only on all our our Macs made things a lot better.

 

[Menopause]

Plot Twist: They renamed discoveryd to mDNSresponder to see if there's placebo effect

 

[Mebsat]

mDNSresponder is dead, long live mDNSresponder

Is it the last version from Mavericks or a newer one?
Could it just be a stopgap so they can focus on non-discoveryd bug reports?

 

[jayducharme]

Back to the roots.
Happy to see Apple scrapping discoveryd and rehauling the whole thing.

I'm curious why they scrapped mDNSresponder to begin with. They must have had a good reason for creating a new network managing system. Obviously, that didn't work out. But Apple rarely backpedals for long. This is probably a temporary fix until they figure out the problem.

 

[diddl14]

Hope they replaced it and not just renamed the damm thing

 

[iamMacPerson]

Awesome! Truth be told I very rarely had Wi-Fi problems but my 13" MBP has had its processor maxed out by Discoveryd in the past. Glad to see its gone!

I installed the beta this morning but haven't really been able to try it out.

 

[PowerBook-G5]

I was just thinking about this a few days ago.

 

[motulist]

I haven't updated my OS since the last 10.6 came out, because there are no compelling new features they've added, but there have been compelling new bugs to be avoided.

 

[adamw]

Good to see a stable DNS back.

 

[C DM]

Hope they replaced it and not just renamed the damm thing

Now that would be something.

 

[TMRJIJ]

Never had issues but I'm glad to hear others are finally able to sustain Wifi connectivity.

 

[ButteryScrollin]

I haven't updated my OS since the last 10.6 came out, because there are no compelling new features they've added, but there have been compelling new bugs to be avoided.

Not having an OS riddled with security vulnerabilities would be a compelling feature to me.

 

[zorinlynx]

I don't know much about mDNSresponder, other than that if you have bad DNS information cached, killing it (and letting it restart automatically) fixes the problem.

 

[blucurv]

Tried it in our office and it works great now. Previously, I had to reconnect every time I closed the rMB lid and opened it somewhere else in the office. It's far more stable now.

 

[TMRJIJ]

Hope they replaced it and not just renamed the damm thing

That would be funny as crap . . . For me because I never had Wi-Fi and I get to read some awesome Apple hate comments on this thread.

 

[quiksand]

What's crazy is that while I never had issues with the process on my Mac, the Discoveryd process would peg the CPU out on my iPhone. I wound up having to turn off continuity on my iPhone in order to get that process under control.

 

[KALLT]

I wonder what took them so long and why they couldn’t get discoveryd to work in the first place. Are the services so radically different that Apple couldn’t reuse some of the source code of mDNSresponder?

 

[azentropy]

Cool, just installed on my 2012 21.5" iMac. On that system often when waking up from sleep it would take a couple of minutes for WiFi to start responding and sometimes even then I would have to manually toggle it on/off or even restart for it to work. In some quick informal testing of manually putting it to sleep and waking up WiFi comes back and responds instantaneously. Will have to see how it does over the next few days...

[EDIT]Yep, sure seems to have solved my problems. WiFi connects and is pretty much immediately available after waking from sleep now! [/EDIT]

 

[steveOooo]

Hopefully 10.11 will work with 'wifi'

Not touching yose***** again, staying firmly on mountain lions furry back

 

[oliversl]

Yes, yes, yes. More rollbacks please. Next, rollback Vista UI.

 

[steveOooo]

I haven't updated my OS since the last 10.6 came out, because there are no compelling new features they've added, but there have been compelling new bugs to be avoided.

Apples policies on bugs summed up in this video http://youtu.be/4WZIzWRbu04

 

[Glideslope]

Well....

...this is good.