Looks like your Mac is running IPv6 but link-local only. Is this the same for your Windows? Is it possible one test is IPv6 and the other is IPv4?
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Slow MacOS gigabit, but fast Windows gigabit. Huh?
- Thread starter WilliamG
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I'm experiencing the exact same issues here -- 2017 iMac running Mojave 10.14.2 on CenturyLink's Zyxel C3000z modem. I saw no changes in a Windows VM but will try Bootcamp tonight. A separate Windows PC has no problems reaching 900+ both directions.
I'm also going to try a dongle on the iMac and a MBP today after work and will report back.
I noticed a similar post on Apple's discussions: https://discussions.apple.com/thread/8419498?page=3
Edit: to bplein, I've played around with IPv6 settings, too, to no avail.
I'm also going to try a dongle on the iMac and a MBP today after work and will report back.
I noticed a similar post on Apple's discussions: https://discussions.apple.com/thread/8419498?page=3
Edit: to bplein, I've played around with IPv6 settings, too, to no avail.
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So the plot thickens: At lunch I brought home my Windows work laptop and it saw the same low speeds my iMac got!
I watched a CL tech yesterday get ~950mbps, with the only difference being that he booted into safe mode to run the tests. Now I'm even more perplexed.
The next steps are booting into safe mode on the work machine, installing Windows 10 via bootcamp on a Mac, and trying the USB3>ethernet dongle on both the iMac and MBP. I'll let you know how it all shakes out, but it seems I'm now further from a solution.
I watched a CL tech yesterday get ~950mbps, with the only difference being that he booted into safe mode to run the tests. Now I'm even more perplexed.
The next steps are booting into safe mode on the work machine, installing Windows 10 via bootcamp on a Mac, and trying the USB3>ethernet dongle on both the iMac and MBP. I'll let you know how it all shakes out, but it seems I'm now further from a solution.
Yeah that makes little sense to me. Are you using the Speedtest Windows app? That's much more reliable in my testing - in Windows.
[doublepost=1548116245][/doublepost]As an addendum, I'm seeing very different speeds (much faster) using Firefox - Speedtest.com, too. This whole thing is very peculiar...
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Progress: Unadulterated Windows 10 install (non-safe mode) on Bootcamp showed it is not a hardware problem. Using Chrome, I saw 920+ going both ways on the built-in NIC.
The next step is to check in with Apple support.
The dongle proved fruitless in macOS.
As to your addendum, I've seen some variation there, too. The fastest speeds I saw on macOS were actually in Safari, and Firefox was generally on par with Chrome. I use Speedtest.com and its desktop app, CenturyLink speed test, Speakeasy.net, Google Fiber speed test, Netflix's fast.com, and DSL Reports' speed test.
The next step is to check in with Apple support.
The dongle proved fruitless in macOS.
As to your addendum, I've seen some variation there, too. The fastest speeds I saw on macOS were actually in Safari, and Firefox was generally on par with Chrome. I use Speedtest.com and its desktop app, CenturyLink speed test, Speakeasy.net, Google Fiber speed test, Netflix's fast.com, and DSL Reports' speed test.
For me Firefox in MacOS is always always the fastest. That said, one of my Speedtest locations is consistently giving me close to full speed. But just that one location. On the Windows side it’s more than one. And real-world speeds are not as fast in MacOS as they are in Windows.
I suspect the reason we don’t see this get much traction is that gigabit is still in the minority’s homes. So...I don’t know how much help we’ll get at this stage.
[doublepost=1548127186][/doublepost]Also, I found it interesting that a USB 3.0 gigabit dongle gave a 2018 mini the boost to regular gigabit speed, but not the 2014 mini.
The whole thing is perplexing.
Yeah, that is super weird about the dongle.
I just got off chat with a couple levels of Apple support, and I'm awaiting a call from a senior engineer tomorrow evening. I'll update this thread when I know more.
I just got off chat with a couple levels of Apple support, and I'm awaiting a call from a senior engineer tomorrow evening. I'll update this thread when I know more.
Chat with an engineer amounted to simply pulling some logs and sending to Apple for analysis, then waiting until Friday for another call. Bummer. However...
I have installers for most of the earlier OS X versions, so I decided to throw some clean installs on an external SSD to see if Mojave was the culprit.
The results:
Mojave clean install saw the same ~500mbps download speeds as my current working install.
High Sierra clean install saw the same ~500mbps download speeds as my current working install and the clean Mojave install.
Sierra clean install saw much closer to advertised speeds/Windows at ~880mbps down.
While I'm glad to have made some progress, this result does not bode well for a true fix. I could start over with a clean install of Sierra on that iMac (and probably will) but I'd like to hear from Apple first. I'm surprised more people aren't seeing this issue.
I have installers for most of the earlier OS X versions, so I decided to throw some clean installs on an external SSD to see if Mojave was the culprit.
The results:
Mojave clean install saw the same ~500mbps download speeds as my current working install.
High Sierra clean install saw the same ~500mbps download speeds as my current working install and the clean Mojave install.
Sierra clean install saw much closer to advertised speeds/Windows at ~880mbps down.
While I'm glad to have made some progress, this result does not bode well for a true fix. I could start over with a clean install of Sierra on that iMac (and probably will) but I'd like to hear from Apple first. I'm surprised more people aren't seeing this issue.
I suspect relatively few folks have gigabit interwebz. Then shrink the number to those running OSX. the result is mostly likely a relative handful of folks.
Exactly this.
Very interesting. I tried the clean install of Mojave and High Sierra - with no improvement. I did not try Sierra.
Thing is, it USED to be fine on Mojave and High Sierra. I’m absolutely sure there’s some incompatibility NOW with CenturyLink, like they’ve done something on their end to cause issues with our NICs.
I’ve had gigabit for over two years, and I’m always running speed tests and moving data around. This change is recent - in the last 2 weeks. Even my iPad Pro - there’s nothing to configure here - is suffering (with the USB gigabit adapter).
Something is going on, but who knows if we’ll find out what it is before the rest of the world joins us in gigabit land.
Well, Apple "engineers" let me down. It took three days for them to review some logs and the suggested fix: Update to 10.14.3 ...lol. I'm a systems engineer myself and I couldn't help but laugh.
They asked me to run a packet capture (running 10.14.3) and send to them, but I highly doubt anything will come of this. I've resorted to wiping everything and going back to Sierra, which I know is not an option for everyone.
Because I only recently had gigabit installed, this was not a "change" for me in the same way you witnessed falling speeds. I feel like this is not an issue with the NIC but instead software-related somehow, which may include iOS based on your findings. I suppose it's possible that CenturyLink is a culprit, but I don't think they're the culprit.
They asked me to run a packet capture (running 10.14.3) and send to them, but I highly doubt anything will come of this. I've resorted to wiping everything and going back to Sierra, which I know is not an option for everyone.
Because I only recently had gigabit installed, this was not a "change" for me in the same way you witnessed falling speeds. I feel like this is not an issue with the NIC but instead software-related somehow, which may include iOS based on your findings. I suppose it's possible that CenturyLink is a culprit, but I don't think they're the culprit.
Hi, I am new here. I am also having similar issue and not sure what to do. I have spectrum gigabit connection and from past few days on my 2018 imac Pro i am only getting around 400-450mbps download speed. I have connected cat6 cable with my Asus GT-AC5300 router which is connected to spectrum modem. The speedtest.net download shows 450mbps at the same time fast.com or google fiber speed test show in 850-930mbps range.
However i have 2018 macbook pro which i connected with usb c- ethernet adapter and it shows 850mbps on speedtest.net also. I connected the same usb c adapter to imac pro but still speedtest.net shows 450mbps. At the same time fast.com and google fiber shows gigabit speed. I dont understand what is happening or which speed test is correct. I think this has started with the new 10.13.4 O.S update. Today spectrum technician came and he checked all cables ,connections etc and said everything looks fine. I have no idea what to do. I changed DNS settings, used google ones etc switched off, hold power button for 10 sec all that stuff but doesn't make any difference.
Any suggestions please. I always used to always get similar speed test results within 50mbps on both imac pro and macbook pro.
However i have 2018 macbook pro which i connected with usb c- ethernet adapter and it shows 850mbps on speedtest.net also. I connected the same usb c adapter to imac pro but still speedtest.net shows 450mbps. At the same time fast.com and google fiber shows gigabit speed. I dont understand what is happening or which speed test is correct. I think this has started with the new 10.13.4 O.S update. Today spectrum technician came and he checked all cables ,connections etc and said everything looks fine. I have no idea what to do. I changed DNS settings, used google ones etc switched off, hold power button for 10 sec all that stuff but doesn't make any difference.
Any suggestions please. I always used to always get similar speed test results within 50mbps on both imac pro and macbook pro.
Since you're seeing the speeds you pay for with two other speed tests, I would think Speedtest.net is inaccurate. Try their macOS app in the App Store, then you'll get a better idea. Also, try DSLReports's speed test to add some data points.
[doublepost=1548694028][/doublepost]Thanks. Dsl reports is showing closer to full speed but fluctuates a lot. But for now I will ignore this issue
Hey, a little late to this party but as it turns out I am having the EXACT same issue as the OP. I have a Mac Pro (Late 2013) running Mojave and MacBook Pro (Early 2015) running Windows 10 through Bootcamp. I have Gb Fiber service through my ISP - Cincinnati Bell here in Cincinnati, Ohio and my network is all run through a Linksys LRT224 and does not use any ISP provided modem.
We started having network issues about a month ago that would require a router restart and it has been getting worse. So I decided to check my speeds this morning and I was only getting ~400Mbs down on my Mac. This was with Safari through my ISP's own speedtest site for just these things. My ping is 2ms - insane I know. I unplugged everything from the router except for the Mac... same deal. I plugged only my MacBook Pro in with a Thunderbolt to Ethernet adapter and instant full bandwith ~960Mbs down - through Firefox.
I too have tried every combination of settings for the Mac ethernet port, tried the Thunderbolt to Ethernet adapter, Jumbo frames, etc and always the same result. Then I tried Firefox and my download speed jumped to ~750Mbs.
In addition, I have two Mac Mini servers running High Sierra and they both are limiting the download speed to the same ~400Mbs.
I unfortunately can't try Windows on Bootcamp on my Mac system as it's a production machine and I can't risk something happening and being offline very long. I also cannot try another version of MacOS for the same reasons.
I am getting fairly confident from my experience and what the other posts indicate - this is a software issue and for some reason, Safari is impacted more so than Firefox. I'm going to do some more testing. I haven't looked too close at intra-lan speeds yet. I have always noticed that Windows default network transfers have always been faster than Mac.
If there have been any other updates from anyone else that can help us narrow this down, please keep this thread going. Thank you!
No update from me, sadly. Just living with it till it gets more traction. You and I both know a LOT of people are experiencing the same problems, but probably don’t realize it.
No solutions here, but just wanted to say I’m having the same problem—downloading capped at around 350 mbps. I’m on AT&T Uverse. The situation got me so perplexed that I started changing my setup! Glad to hear that it’s not just me. I realize that 350 down is a decent speed, but it’s not what I pay for. I’m happy I saw this thread because I was about to set up an AT&T service call, but AT&T charges for the visit if there is nothing wrong with their equipment.
Maddening.
Maddening.
I've had this exact issue since I got gigabit like 3 or so years ago 450 or so down / 950 or so up.
Tech comes over with PC gets 950 down/950 up, I'm typing this on a cheap Windows laptop where I just got 930 down/700 up
Here are a few more puzzle pieces if this helps anyone.
My 2009 iMac has the same issue.
The most notable thing is that when booted into Bootcamp I get 900+/900+ so it can't be the hardware
Tech comes over with PC gets 950 down/950 up, I'm typing this on a cheap Windows laptop where I just got 930 down/700 up
Here are a few more puzzle pieces if this helps anyone.
My 2009 iMac has the same issue.
The most notable thing is that when booted into Bootcamp I get 900+/900+ so it can't be the hardware