I have a Voyager enclosure attached to my Mac Pro via eSata, with a WD 2 TB drive in it right now. I'm copying about 500 GB of media from one of the internal drives to the Voyager, and I'm seeing a copy speed of 4 MB/s, which is incredibly slow. It's telling me it will take "about a day" to copy 500 GBs. That's not right. Any idea what could cause a slow down like this?
Got a tip for us?
Let us know
Become a MacRumors Supporter for $50/year with no ads, ability to filter front page stories, and private forums.
Slow copy speed with external eSata Voyager enclosure
- Thread starter badlydrawnboy
- Start date
- Sort by reaction score
I think the eSata card is bad. I used a FW800 cable to connect the Voyager enclosure to the Mac Pro, and the copy speed went way up, i.e. 40 MB/s.
A bad or subpar cable, or one that is too long, or a bad circuit in the external box could also be bad.
Then it could just be the card. Dunno how much interest you have in finding the issue but Try a different cable. I've seen a lot of issues with them.
Then it could just be the card. Dunno how much interest you have in finding the issue but Try a different cable. I've seen a lot of issues with them.
Good point. Which brand of eSata cable have you had the most luck with? And what do you mean by "too long"?
This is getting even more confusing.
Last night I hooked up the Voyager to FW800 and was able to copy data very quickly, i.e. 40 MB/s.
This morning, I tried copying data from another internal drive to the Voyager with the same FW800 cable, and the transfer speed was 3 MB/s. The internal drive is a 480 GB SSD, very fast. The drive in the Voyager is the exact same one I was using last night: a WD 2TB Caviar Green.
Maybe the problem is with the enclosure and not the eSata card or cables. Not sure why it works in some cases and not others, though. My head hurts trying to figure this out.
Last night I hooked up the Voyager to FW800 and was able to copy data very quickly, i.e. 40 MB/s.
This morning, I tried copying data from another internal drive to the Voyager with the same FW800 cable, and the transfer speed was 3 MB/s. The internal drive is a 480 GB SSD, very fast. The drive in the Voyager is the exact same one I was using last night: a WD 2TB Caviar Green.
Maybe the problem is with the enclosure and not the eSata card or cables. Not sure why it works in some cases and not others, though. My head hurts trying to figure this out.
That's the next step. Thanks.
----------
Just tried something else. I put a brand new Hitachi UltraStar 7200 (very fast drive) into the Voyager using the same FW800 cable and did a transfer. Got 50 MB/s on this one.
So, it would appear I either have an intermittent problem with the Voyager, or the issue is with the Caviar Green drive.
For what it's worth, I've had to return the Voyager Q twice so far. OWC is good about it, replacing it with free shipping, but I'm on my third one in a couple years now. In my case, both times, the dock simply stopped recognizing any drive. Never seems to matter what cable / interface is used.
That's good to know.
What kind of transfer speeds should I expect with eSata and the Voyager using fast hard drives?
I use an app called SuperDuper to backup/clone drives. Going from one internal HD or SSD to another, I get transfer speeds of about 100 MB/s. What should it be going from the internal drives to a fast drive in the Voyager via eSata?
If its working properly, you will get the same speeds with external eSATA as between internal drives. Depending on the eSATA card you may actually get a bit more.
For reference, I have a NewerTech MAXPower eSATA 6G PCIe 2.0 Controller Card with two Hitachi HDS5C3020ALA632 2TB drives in a OWCMESATATBEK dual bay enclosure and the data transfer is fast. I use it to store and backup tons of large video files and the transfer is quick. I have the data transfer rates somewhere, I'll have to look for them. The eSATA links from the card to drives negotiate at 6gbps. This card requires no drivers. The card and enclosure ran me about $80 total in 2011.
For reference, I have a NewerTech MAXPower eSATA 6G PCIe 2.0 Controller Card with two Hitachi HDS5C3020ALA632 2TB drives in a OWCMESATATBEK dual bay enclosure and the data transfer is fast. I use it to store and backup tons of large video files and the transfer is quick. I have the data transfer rates somewhere, I'll have to look for them. The eSATA links from the card to drives negotiate at 6gbps. This card requires no drivers. The card and enclosure ran me about $80 total in 2011.
Last edited:
Interesting.
I zeroed out my backup drives and installed the eSata card in a different slot. Seems to be working better now, but still get lower speeds (i.e. 75 MB/s) than with an internal transfer (>100 MB/s).
I wonder where the bottleneck is? Could it be the Voyager enclosure itself? Maybe the cables that came with it (or that I bought from OWC; can't remember which)?
----------
Actually, scratch that; I'm only getting 58 MB/s now on an active transfer to the Voyager via eSata.
----------
FYI I have the same card.
I zeroed out my backup drives and installed the eSata card in a different slot. Seems to be working better now, but still get lower speeds (i.e. 75 MB/s) than with an internal transfer (>100 MB/s).
I wonder where the bottleneck is? Could it be the Voyager enclosure itself? Maybe the cables that came with it (or that I bought from OWC; can't remember which)?
----------
Actually, scratch that; I'm only getting 58 MB/s now on an active transfer to the Voyager via eSata.
----------
FYI I have the same card.
A Crucial M4 SSD in the Voyager, connected via eSATA to a Caldigit FASTA-6GU3 in my Mac Pro, got 168MB/sec write, 246MB/sec read speeds.
The same M4 SSD hooked directly to my Areca RAID card got 281MB/sec write, 456MB/sec read speeds. When I hooked that same M4 to the Voyager again via USB 3.0, it was nearly identical to the eSATA speed, so I concluded that is the fastest speed possible between the Caldigit and Voyager combo.
These speeds were found using AJA System Test, set to 16GB file size, video frame 1920x1080 10-bit, file system cache disabled (checked).
Whoa! I just ran a backup with SuperDuper from a 480 GB OWC Mercury Extreme pro to an external 2 TB WD Caviar Black in an OWC enclosure. Transfer speed started out at 5,000 MB/s then dropped throughout the backup. At the end it said the average was 600 MB/s.
That's way faster than what I get with an internal transfer with the same drives.
Then I did a backup of my internal Hitachi UltraStar 2 TB 7200k internal drive to another partition on that same external Caviar Black drive. In this case, the transfer speed was only 75 MB/s from the start, and dropped to 50 MB/s toward the end.
Is that an expected speed difference between the SSD and the HDD? Doesn't seem right to me; the UltraStar is a pretty fast drive.
That's way faster than what I get with an internal transfer with the same drives.
Then I did a backup of my internal Hitachi UltraStar 2 TB 7200k internal drive to another partition on that same external Caviar Black drive. In this case, the transfer speed was only 75 MB/s from the start, and dropped to 50 MB/s toward the end.
Is that an expected speed difference between the SSD and the HDD? Doesn't seem right to me; the UltraStar is a pretty fast drive.
What I meant is that 600MB/s is not 600Mb/s.
600Mb/s actually is 75MB/s, which makes sense of a Caviar.
Loa
The problem is that SuperDuper! does something they call "smart update" which only copies things that changed. It then displays an "effective" transfer rate, which jumps up to thousands of MB/sec when it skips over things it doesn't need to copy.
If you did a clone, and then changed one byte of data, and redid the clone, it would be done in a flash, and say it did the transfer in 5000MB/sec, or maybe more.
If you did a clone, and then changed one byte of data, and redid the clone, it would be done in a flash, and say it did the transfer in 5000MB/sec, or maybe more.
Ah, makes sense.
I just did a test using the AJA System Test with the same parameters you mentioned. For an internal transfer I got 127 MB/s read and 130 MB/s write. For an external transfer to a 7200k 2 TB drive via eSata and OWC enclosure, I got 105 MB/s read and 107 MB/s write. For external transfer to a Caviar Black 2 TB drive in the Voyager, I got 102 MB/s read and 104 MB/s write. That makes a lot more sense. Thanks for helping me figure this out. Seems everything is running as it should be.
Question, though. Does AJA System Test automatically run the test from the boot drive?
You can choose any attached volume to run the test on, but as a default, it would probably choose either the boot volume, or the last connected volume that was tested.