Apple Replaces Problematic 'Discoveryd' Process With mDNSresponder in 10.10.4 Beta 4
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 As noted by MacRumors forum members and 9to5Mac, in OS X 10.10.4 beta 4, the discoveryd process has been replaced by mDNSresponder.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.
Popular Stories
Apple may have canceled the super scratch resistant anti-reflective display coating that it planned to use for the iPhone 17 Pro models, according to a source with reliable information that spoke to MacRumors.
Last spring, Weibo leaker Instant Digital suggested Apple was working on a new anti-reflective display layer that was more scratch resistant than the Ceramic Shield. We haven't heard...
This week marks the 10th anniversary of the Apple Watch, which launched on April 24, 2015. Yesterday, we recapped features rumored for the Apple Watch Series 11, but since 2015, the Apple Watch has also branched out into the Apple Watch Ultra and the Apple Watch SE, so we thought we'd take a look at what's next for those product lines, too.
2025 Apple Watch Ultra 3
Apple didn't update the...
Apple has completed Engineering Validation Testing (EVT) for at least one iPhone 17 model, according to a paywalled preview of an upcoming DigiTimes report.
iPhone 17 Air mockup based on rumored design
The EVT stage involves Apple testing iPhone 17 prototypes to ensure the hardware works as expected. There are still DVT (Design Validation Test) and PVT (Production Validation Test) stages to...
Apple will likely manufacture its 20th anniversary iPhone models in China, despite broader efforts to shift production to India, according to Bloomberg's Mark Gurman.
In 2027, Apple is planning a "major shake-up" for the iPhone lineup to mark two decades since the original model launched. Gurman's previous reporting indicates the company will introduce a foldable iPhone alongside a "bold"...
While the so-called "iPhone 17 Air" is not expected to launch until September, there are already plenty of rumors about the ultra-thin device.
Overall, the iPhone 17 Air sounds like a mixed bag. While the device is expected to have an impressively thin and light design, rumors indicate it will have some compromises compared to iPhone 17 Pro models, including only a single rear camera, a...
While the iPhone 17 Pro and iPhone 17 Pro Max are not expected to launch until September, there are already plenty of rumors about the devices.
Below, we recap key changes rumored for the iPhone 17 Pro models as of April 2025:
Aluminum frame: iPhone 17 Pro models are rumored to have an aluminum frame, whereas the iPhone 15 Pro and iPhone 16 Pro models have a titanium frame, and the iPhone ...
Apple is preparing to launch a dramatically thinner iPhone this September, and if recent leaks are anything to go by, the so-called iPhone 17 Air could boast one of the most radical design shifts in recent years.
iPhone 17 Air dummy model alongside iPhone 16 Pro (credit: AppleTrack)
At just 5.5mm thick (excluding a slightly raised camera bump), the 6.6-inch iPhone 17 Air is expected to become ...