Q: Time Machine extremely slow on Mavericks ?

Over 3000 views and 74 repiles to this thread. Clearly there is an issue with Time Machine in Mavericks - I think we all need to contact Apple support directly and tell them to get a move on with a fix for this *extremely important* issue. What use is a backup system that doesn't work?

I have contacted Apple support three times, and have not been given a satisfactory solution to the problem - verify the Macintosh HD, verify the backup HD, wipe the backup drives and start again (see elenchus' excellent post above), clean reinstall of Mavericks (from a backup that has never completed!)...

Strange thing is, my wife's (older) iMac is having no problem backing up with Mavericks to the time capsule or to USB, but as I alluded above, the backup on my mid-2011 iMac with 12 GB RAM has never completed... I stopped when the new backup of 670 GB had reached just under 1 TB in size, and was continually updating the amount to be backed up, so there is clearly duplication of files being backed up.

What I've done as an interim solution is buy CCC to replace Time Machine, until Apple sort the problem out.

I've gone from 23hrs remaining to 9hrs remaining - in the space of twenty minutes?!  This might actually work.

Still doesn't explain anything though

And now in just 50mins I'm down to just 2hrs remaining for a full backup.

So one of the five or six actions I performed as per previous posts did actually fix this issue...

Yes same problem here. Surely there must be a software issue. I was backing my system up fine to a WD MyCloud. SInce the update to Mavericks Time Machine is extremely slow. I ended up deleting the old file and starting again from scratch. However still taking more than a day to carry out first backup of around 400Gb. There is no problem with writing to the drive as I uploaded a 1.2Gb movie in about a minute so the problem appears to be Time Machine.

I'm having a similar problem.  I'm backing up to a usb external hardrive and the "prepairing backup" stage takes a long time.  Then the write speed is also very slow.

Like everyone, I'm having the same problems on my iMac 2013 16G SSD + WD MyBookLive directly connected via Enet.  Lost all TM bkups under Mt Lion.  Reformated WD drive, new TM archive took 3 days to do 1st bkup of 286GB, has only been able to do 1x new bkup per day since do to inordinately slow process.  Only 4 bkups since Friday's reformat and rebuild!! Consequently no hrly bkups.  TM seeing 80 to 150GB each time and taking several hrs to run, though I'm only using internet and very small files.  Should be only MB of changes.

This is ridiculous.  Really wished I'd stayed with Mt Lion

on my MBA late 2010 I had/have the same issue(s) - updated to Mavericks and TimeMachine just stopped working at all - all the issues described above.

Tried everything including resetting the TimeCapsule but...

Restarted the backup yesterday using my LAN connection - ~30 GB in 24 hours

After reading RickKavanagh's post above I just enabled WiFi and unplugged the network cable - the backup continued and now I'm on 70 GB - so ~40GB in aprox. 1 1/2 hours

still more then 100GB to go - but compared to the speed I had the last days using LAN this is FAST

me either. I am desperataly waiting for a backup on my TimeMachine... to me, this move to Mavericks is somehow a mess :-(

I have had the same problem.

It is worrying when you see estimates of 9 hours to finish and slow progress at first, but mine got back to normal after the first BU. One good tip , I have seen in this thread is to archive your old TM backup before you install MAvericks , set up a new disk/partition and make a new TM backup.

Note also that the TM icon does not spin anymore. Just a small arrow appears when a backup is happening.

Update: complete initial backup (170 GB) finished within ~3hours

This makes absolutely no sense. I started my backup (USB drive, Airport Extreme , Mavericks) and experienced the same problem. It took a day to backup 88GB out of 700+ BG. Stopped it, reformatted and restarted fresh. Same snail speed. I stopped that bakup, rebooted, resumed backup and now Time Machine backed up 3.4 GB in about 5 minutes. Hopefully it stays at that rate. If it does my first full backup may take under a day.

And by the way, I really miss the spinning clock icon...

UPDATE: 2 hrs, 50 GB. Again, all I did was stop a backup in preparation, restarted my MBPr and restarted the backup process.

I noticed last night, that after the initial backup - which took 18 hours - during subsequent back attempts, which were GLACIALLY slow, that if I waited for preparing backup to be finished and when the glacially slow backup had begun, that if I opened the TIME MACHINE preference pane and turned the backup "switch" off and on again, then the backup would resume at a more normal and fast speed.  Turning it off and on during preparing backup did not speed things up however.... 

OK, after 3 chats and a call to the Apple Support Centre, I think I've sorted the problem out.

There are two critical steps.

1. Delete the file Macintosh HD/Library/Preferences/com.apple.TimeMachine.plist

2. Rename the backup drive (Time Machine, in my case) using Airport Utility. (If you're not using Time Capsule, just try renaming the backup drive to [Whatever1], and this will probably do the trick)

3. Reboot the Mac

4. Restart Time Machine and assign the newly named backup drive (in my case, "Time Machine 1").

5. Start the backup.

6. Presto! A backup that was not getting close to completing after 3 days (in fact, it was just adding more and more to the initial backup) has completed over 150 GB backup in just under 2,5 hours. I still have 400 GB to backup, but things are looking much more promising...

Essentially, the procedure is removing all TM's references to the backup drive and reassigning them as if it was a new drive.

ANother 15 GB has been backed up in the 10 minutes it's taken me to write this. Looking good!