rMBP Time Machine Speed -- Normal?

mneblett

macrumors 6502
Original poster
Jun 7, 2008
369
0
Not sure whether to post here or in Peripherals, so I'll start here.

I have a late '13 15" rMBP and an 802.11ac 2TB Time Capsule, directly connected by CAT6 cable (via an Apple Thunderbolt-to-Ethernet adapter).

I never see Time Machine back up speeds over 20-21 MB/s (160-170 Mb/s) on a network that is theoretically capable of 125 MB/S -- usually lower. While I recognize that initial file transfer speeds are often slow (KB/s range), after the first minute or so they ramp up to the 10-20 MB/s range. I am also aware that real world never equals theoretical (overhead, signal/noise issues, etc.), but I was expecting a bit better than 15-20% of theoretical!

As I often have my 40GB Parallels Win 8.1 file in the back up, TM backups can take a fair amount of time (I am aware that I can exclude the Parallels file, but do not wish to do so).

So, is my experience "normal"? How do others' set-ups compare? Is it possible that I've missed a setting that would enhance the data rate?
 

Meister

Suspended
Oct 10, 2013
5,455
4,265
I called apple care about this.
My macmini backs up normally but the rmbp takes not hours but days :eek: !
Apple said that is normal unless i turn off the encryption.
 

snaky69

macrumors 603
Mar 14, 2008
5,903
480
Hard disks in time capsules are usually the slower "green" drives. I haven't seen much higher than 20MB/s or so write speed to them.
 

mneblett

macrumors 6502
Original poster
Jun 7, 2008
369
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Hard disks in time capsules are usually the slower "green" drives. I haven't seen much higher than 20MB/s or so write speed to them.
I suspect you've hit the nail on the head.

Time to look into whether a 7200 rpm HD (or even an SSD if I'm feeling stupid with my $) would provide enough of a performance boost to make the effort worthwhile.
 

mneblett

macrumors 6502
Original poster
Jun 7, 2008
369
0
A little more research resulted in finding:

The A1470 Time Capsule that ifixit took apart had a SATA III Seagate Barracuda ST2000DM001. Seagate specs read/write data rates at 156MB/s, max 210MB/s -- exactly right for ~20-21MB/s Time Machine back-ups from my rMBP.

Now it's off to look for data rates from SSD's :D
 

maflynn

Moderator
Staff member
May 3, 2009
63,988
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Boston
I found TM to be exceedingly slow across the network, regardless of the destination, i.e., NAS or TC. When I started using a Drobo Mini DAS, well things changed dramatically and my backups took minutes, in fact the initial backup which could take a day or two finished up in 40 minutes.
 

laurihoefs

macrumors 6502a
Mar 1, 2013
792
22
A little more research resulted in finding:

The A1470 Time Capsule that ifixit took apart had a SATA III Seagate Barracuda ST2000DM001. Seagate specs read/write data rates at 156MB/s, max 210MB/s -- exactly right for ~20-21MB/s Time Machine back-ups from my rMBP.

Now it's off to look for data rates from SSD's :D
Just like you quoted, the Seagate specs sheets state speeds in MB/s, not Mb/s. So 210MB/s > 21MB/s.

The drive is not the bottleneck here. The processing power of the TC, and file system/transfer method are much more likely the limiting factors, and there's not much that can be done to those.