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- Does Time Machine Backup Applications
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- What Does Time Machine Backup
Time Machine will only backup drives that are formatted to HFS+ and now also APFS. And please don't believe all the blah talk about how Time Machine doesn't work, etc. Time Machine is a good backup program and does work well. Time Machine is used to back up your Mac completely. It includes apps, music, system files, emails, photos, videos, and all your documents. When you turn on the machine, it will start the hourly, daily, weekly backups automatically. How Does Time Machine Work on Mac.
Time Machine was and remains one of the best tools to backup Mac’s data. While the tool itself is straightforward and does not have manyoptions, at times, it is so frustrating to figure out why it misbehaves.
If time machine backup is slow on your Mac and you arelooking for ways to improve the speed of the backup then this article is foryou.
How long it takes to do a Time Machine backup depends on thefollowing factors:
The Number of Files and Their Size on the Primary Storage
How long does time machine take to backup 500gb? With allfactors being the same, it is obvious that 500GB will take longer to back upthan 256GB. And it doesn’t matter how big the drive is. What matters is howmuch data the disk contains.
And it’s not just the size. The disk that has 10,000 fileswill take longer to back up than the drive with 1,000 files assuming that theytake up the same space in both cases.
The Priority of the Backup Process and How To Adjust It
The Time Machine app was designed to work on the background.The idea is that if the Time Machine is set to run automatically, the lastthing you want it to use a lot of CPU while you are working on somethingimportant. So, by default, the backup process is a low priority one, and itshould remain so.
However, if you are planning to do something disruptive,such as installing a new macOS or do experiments as I do – sometimes I installapps with viruses to see their impact and then report the results on my site.In this case, I’d love to take a full backup immediately, and I don’t want towait for too long.
Unfortunately, the background nature of the Time Machinedoes not work in situations like this.
Naturally, I want to change the default behavior and pushthe backup app to the foreground at the expense of other processes on Mac.
I found two ways to change the Time Machine processpriority.
- Remove throttling for low priority processes
- Change the priority of the backup task
Remove throttling for low priority processes
![How does time machine work How does time machine work](https://community.netgear.com/ejquo23388/attachments/ejquo23388/readynas-use/176905/1/Screen Shot 2019-01-06 at 2.57.32 PM.png)
As we already know, the Time Machine process, by default, is a low priority process. And macOS treat such process differently than regular processes. It artificially throttles them in order to give other (high priority) process more CPU time.
With this approach, you can play your game or watch a Youtube video in the browser without interruptions from system background processes.
But since our goal was temporarily to speed up Time Machinebackup, we can use a little trick that overrides the default macOS behavior.
The steps are the following:
1. Start Terminal app
2. Copy following text and paste into the Terminal window
The command requires entering an admin password. If youdon’t have a password enabled when logging in, you have to set it up in SystemReferences -> Users and Groups.
The command will take effect immediately.
3. Now open Time Machine and click the Backup Now button tostart the process.
4. After backup finishes don’t forget to change the setting backby running the same command with different parameter:
According to some people, the backup time reduces significantly, and in some cases, users reported the reduction from 11 hours to 55 minutes.
I tested the command myself, but I didn’t see that muchdifference. The improvement was around 20%. I believe that it really depends onthe size of the backup. The bigger the size, the bigger is the improvement.
Caveats:This command is system-wide. It means the change will apply to all system processes. So, if you have other background processes that run with a low priority, they will suddenly start taking more CPU.
That’s why either turn it off after backup is done bysetting the parameter to 1 or simply reboot the Mac.
User-friendly approach
If you don’t like to use Terminal, there is an app that calls command above for you. It’s called App Tamer by St. Clair Software. The app has a checkbox called “Accelerate Time Machine Backups”. The app is not free, however.
Change the priority of the backup task
Another way to change the priority of the backup processalso requires some Terminal magic.
In macOS, it is possible to set the task priority higher orlower. The tweak is called niceness, and macOS (just like other UNIX systems)has two commands: nice and renice. With nice command, you set the initialpriority, with renice you change it for the currently running process.
Here’s how to change the priority of the backup process:
- Open Activity Monitor
- Make sure that the PID column is visible. Go to View->Columns menu in the menu bar (menu at the top of the screen) and enable Process ID.
- Sort processes in the list by Process Name and find the backupd process. Note its PID. In my case, it was 5200.
- Run following command in the Terminal:
where <PID> is the value from the Activity Monitor, so for me the command was
Note the value under NI column. By default, this value isalways 0.
So, now we can change niceness and adjust priority higher orlower. The acceptable range of values is from -20 to 20.
To set the priority higher the value should be lower.
To set the priority lower the value should be higher.
Since we want to increase the priority, we will set thevalue to -20 (the lower the value, the higher is priority).
Here is the command:
Again, replace <PID> with the value from the Activity Monitor, like this:
Does Time Machine Backup Applications
User-friendly approach
There was an app called ProcessRenicer from eosgarden, which could do it in a visual way without having using the Terminal app. Unfortunately, the app is not being maintained anymore. So, I am not sure if you can make it work on the latest macOS versions. However, if you still on older OS X versions, it might work for you just fine.
Both approaches described above have some limitations. Whilewe were able to eliminate the wait time and make sure that Time Machine isworking as hard as possible, this may not be enough.
In the simplest form, the backup process is reading datafrom one disk and writing it on another. So, the speed of the backup depends onthe read speed of the primary storage and write speed of the backup drive.Also, in the case of AirPort Time Capsule or NAS, it depends on the networkspeed.
The Speed of The Primary Storage Drive
The speed of the primary disk on Mac varies widely from onemodel to another. Generally, MacBook Pro disk is faster than MacBook Air,models with SSDs are faster than models with HDDs, and newer Mac models arefaster than their predecessors.
When I was testing the impact of a FileVault on the diskperformance, I tested the disk performance on various Macs I had at home. Therange was from 81.7 MB/s on Mac Mini 2012 to 1885 on MacBook Pro 15-inch 2016.
You may say that that the disk in the Mac cannot bereplaced. That’s not necessarily true. It is true for MacBooks Pro built after2015 and MacBooks Air built after 2017, but older models are upgradeable.
What’s cool is that besides getting a larger disk, you getinsanely fast speeds as well.
Let’s what I mean on the example of upgrading my MacBook Air2014. Currently, it has a 128GB disk, and the read performance is 314 MB/s.
There are multiple storage upgrade options on the market.Two brands are among the best in particular: OWC and Feather.
What Does Time Machine Backup Includes
For instance, this 512GB Feather SSD compatible with my MBA increases read performance up to 3100 MB/s. That’s a 10x increase in speed!
And a little bit more expensive 480 GB SSD from OWC boasts read speeds up to 3200 MB/s.
Replacing SSD is very easy, even I can do it!
Note: Make sure to read compatibility notes for SSDs.Feather has a nice chart in the description which tells which of their productsis compatible with which Mac.
Another way to check the upgradeability of the Mac iscrucial.com. I’ve been using their scanner for decades when I needed to knowwhich HDD or RAM is compatible with my computer.
The Speed of the Backup Drive
The good thing about upgrading primary storage and improvingits read performance is that Time Machine is not the only thing that benefitsfrom the upgrade. Literally, every app runs faster (possibly 10x faster) now.
However, when it comes to the backup process, the biggestbang for the buck is choosing the right external hard drive.
For instance, I tested the difference in performance between backing up on an external hard drive and on a thumb drive.
Didn’t you know that it is possible to backup on a flash drive? Yes, you can. Flash drives work exactly the same way as external hard drives. The difference is usually the speed: flash drives are usually way slower (sometimes 10x-30x slower).
As expected in my experiment, the flash drive performed very poorly. I compared the performance of a generic cheap thumb drive (no brand name) with a Toshiba Canvio Basics 4TB Portable External Hard Drive.
Since my flash drive was limited to 32GB, I backed up a brand new MacBook without any applications installed. The backup size was around 20GB.
Here is the difference performance:
- It took 59 min (almost an hour) to back up 20GB with Time Machine on a cheap flash drive.
- On the other hand, it took 38 minutes to do the same backup on Toshiba external HDD (35% less time).
Conclusion
We reviewed several ways to speed up Time Machine backups.
Some of them didn’t require any financial investments:manipulating backup process priority.
Others require purchasing extra hardware, and they generallyprovide long term benefits.
If you need recommendations for the best external devicesfor Time Machine, you can find them below. But even if you decide to go withdrives other than I recommend, please go with well-known brands.
Never buy hardware with a name you can’t pronounce, such as Junlipu or Shenmazan. Note: these are not real names, I just made them up, but you get the point.
I am just amazed at how unknown brands get thousands of 5-starreviews on Amazon, and I try to stay away from those.
Remember, losing a backup may be much more costly thaninvesting in a more expensive but reliable brand.
Here is my list:
- Best Thunderbolt Drive For Time Machine
Time Machine uses a unique ID (
UUID
), which is specific to a volume (i.e. a partition of a disk), to associate the volume with its backup. In OS X releases before 10.7 Lion, when people exchanged their disk or migrated to a different Mac, this feature has made it difficult to get Time Machine to continue adding to the backup history of the previously used disk.In OS X Lion and now also OS X 10.8 Mountain Lion, there is a nifty new Terminal command called
tmutil
, which makes this whole drama a breeze. What is logic.In general, the stubborness of Time Machine is meant to prevent data loss in cases such as when a different disk with the same name is attached to your Mac. Thanks to the different
UUID
, Time Machine detects that this is in fact not the same physical disk and will not add a new snapshot to the backup history of your own volume.Nonetheless, there are a few cases, where this is exactly what we want.
The most popular use case will be when you migrate your data to a new volume, either on the same disk or a different disk, or even different machine, and you know that you will not be taking any more backups of the previous volume.
In those cases, it can be desirable to associate the new volume with your backup history.
Let’s say the hard drive of your clunky old MacBook is called
Macintosh HD
the MacBook is called John Doe's MacBook
, and it is backed up to an external disk called Time Machine Disk
. In this case, the backing store (Machine Store
in tmutil
lingo) of your MacBook is at /Volumes/Time Machine Disk/Backups.backupdb/John Doe's MacBook
and the latest backup of Macintosh HD
is at /Volumes/Time Machine Disk/Backups.backupdb/John Doe's MacBook/Latest/Macintosh HD
.How Does Time Machine Work
Now you migrate to a blazing fast new SSD, but for sake of simplicity, you still call it
Macintosh HD
because you erase and sell your old hard disk. Naruto ultimate ninja heroes 3 ppsspp iso for pc.After the migration, Time Machine thinks that you have a completely new disk and will start a fresh backup. In the process, it will likely erase almost all of your existing backups to make space.
That’s certainly not what you want. You would like Time Machine to simply inherit the existing backups in order to be able to browse those old backups in the future and possibly restore some files. Moreover, instead of creating an entirely new full backup from your admittedly brand new disk, future backups should just be added as incremental backups to the existing backup history.
To accomplish this, a single command with
tmutil
is sufficient.The following command permanently manipulates the association of your Time Machine disk. Use it only once you understand what this means. You proceed at your own risk.
Please make sure you understand what this does and read the
man
page of tmutil
(run man tmutil
in a Terminal).Here is the description of the
verb
associatedisk
, which we will use for this purpose:What Does Time Machine Backup
Note that the notation
[-a]
in the man page indicates that -a
is an optional parameter: The -a option tells associatedisk to find all snapshot volumes in the same machine directory that match the identity of snapshot_volume
, and then perform the association on all of them. This means either of the following are correct, depending on your needs.Only associate a single snapshots
Associate all snapshots (what you normally want):
You will probably be prompted to enter a password. Type you regular OS X login password. The characters you type won’t be displayed, that’s to be expected.
Again quoting from the
man
page: