Q: time machine very slow with mountain lion

I ran tmdiagnose twice, once while connected by Airport, and once by Ethernet. Still no fix. Airport backups are normal and Ethernet backups are painfully slow.

I don't doubt there's some helpful info in all those reports it produces but I don't have the expertise to understand them.

Glad it's doing something to help some folks, but we don't have a universal cure yet.

Crazy enough, the sudo-thing absolutely helped!

(New Macbook Air connected via USB to Seagate HD)

After the terminal-sudo and a restart, now everything running at normal speed instead of superslomo just 5 minutes before...

Thank you!!!

TMDiagnose did not improve my backup speed over wifi (mid-2008 MacBook Pro, 10.8).  I read through the Terminal output and didn't see that it should have any effect, unclear why it's working for others.  Not a panacea, but no harm done I suppose.  Was not having speed trouble over ethernet, but will report here if it changed for better or worse after running the utility.

I too have painfully slow backups after upgrading to Mountain Lion on my MacBook Pro (mid 2010). Few megabytes of backup that used to take seconds would now take 30 or more minutes. The backup is over wifi that connects at 300bps. I am pretty sure it's not the network. All other network activities are pretty speedy. I also tried tmdiagnose without success. My next step is to reintall Mountain Lion...

So,I reinstalled Mountain Lion. The initial full backup of 144 GB over gigabit wired network took 2 hours. Tried an incremental backup of 7 MB. That took seconds over the wired netwrok. Next, I tried WiFi backup of 64 MB. That took over 30 minutes. At this time, I decided to switch form 5 Ghz N network I was on, to 2.4 Ghz N network. The last backup of 500 MB took about 5 minutes! Not sure why this would make any difference since the 5 Ghz had better signal and connected at a higher rate (300 vs 130).

So reinstalling didn't help for me. But switching from 5 Ghz network to 2.4 Ghz network made a huge difference.

The 5Ghz band can be much faster, but only at very limited distances.

Using the 2.4 one is much more reliable to devices who are located farther from eachother.

You might experience data drops using the 5Ghz band I guess.

The most reliable connection you get with 1Tbit UTP cable cat. 6, thats beyond question.

I didn't read all 96 posts but I had the same problem. Even initialised my Time Machine disk, but I could see in the Activity tool that the disk activity was next to zero (below 1 MB/s).

I just found it: It was my anti-virus software (Sophos in my case) that first scannes every file that is handled. Since my disk is scanned already, scanning a backup is overkill. I disabled it (temporarely of course) and now it's crunching away at up to 60, 75 MB/s. Any of you using anti-virus software?

Just confirming the sudo command worked for me - 700Gb backup was going to take 13 days, it's more like 13 hours now. Thanks for the tip!

sudo tmdiagnose - plus several reboots - didn't work for me.

TM on Snow Leopard worked ok... but following the upgrade worked once.

Now a full overnight backup has gotten "faster" with tmdiagnose, but it increased from 125MB of 21 GB, to 863MB of 22GB backed up after an overnight soak.

I'm running a late 2011 MBA connected to a MyBook Live Duo via WPA2 wireless.  I also have Filevault active, but I had that running under Snow Leopard, too.

And I doubt it's the network, as I can transfer files via Finder back and forth over the network without any delays.

There are several programs running in the background that could affect a TM backup.

Virussoftware is one, Little Snitch for instance is another.

Any Apple engineer can look at the output of the tmdiagnose, and tell you what is troubling you so far.

But you can start checking yourself, for instance by sighning with shift pressed, it will disable all logon items, so you have a more leaner system to run from.

Tried the shift-key login, and I've had Sophos off... and I got a progress bar, and a reboot (no Finder).  Started the backup again just to try it out, and I'm up to a whopping 3.7MB of 21.4 GB in 5 hours.

Odd thing is, looking into the Time Machine itself, it looks like I have multiple copies backed up from just today.

This is my second post. My configuration is a MacPro connected (USB 3.0) to a Drobo where the TM bundles reside. I back up my Macbook Pro (though a wifi connection to the MacPro - Airport). TM is exptremely slow (unusable to for the Macbook). The TM speed on the MacPro, whichis directly connected to the Drobo is blazing as usual. Both machines are running Mountain Lion.

I have run the "sudo tmdiagnose" process on both machines and rebooted. But the speed of a TM backup on the Macbook is still unusable (4+ Days for 11 Gig). I didn't have this issue with Lion. And I have disabled any protection software (Snitch).

There are no problems with file transfers to the Drobo from the Macbook.

This seems to be related to a TM conection over wifi.

10.8.1 is out, maybe it will fix this problem?

Didn't for me :-(

Hi,

Yesterday evening, I have installed 10.8.1 update and this morning Time Machine backup was done (135 GB).

Before update I was still at 1.8 MB transferred in several days...

I will test again this evening.