Hey all,
So someone gave me an old server they were using in their office, and I am using it as a home server. It's an older single core Xeon machine with a 4 port RAID controller, and 4 more Sata 1.5gb/s connections on the MoBo. I have several drives I was using, via USB into my time capsule or even just tossed aside and not used. But this had enough space for me to stick all of my drives in it!
So my question was in regards to speed, and speeding up performance over gigabit ethernet. I'm not working with 4k video or anything else like that, but I am working with a lot of DSLR images so being able to saturate GbE would sure be nice.
Now, maybe my math is all wrong or there is a major concept I'm not understanding, but here's the issue. Internally, most of my drives (I'm running Ubuntu server, so via OS X terminal I SSH into the machine and run hdparm) run around 100MB/s. Currently, I have a RAID 1 array of two of the original drives (80GB) included in the machine, which is for the OS. Then I have a 2TB, 1TB, and 500GB drives mounted inside. The fastest is the 2TB drive, I just ran hdparm and got back a 'buffered disk speed' reading of about 114 MB/s.
Now, via GbE to either my desktop or my MacBook pro (Router is an Apple Time Capsule, which feeds into a GbE switch at my desk that feeds both the desktop and the laptop, router is on the other side of the room directly attached to server, printer, and modem), I get about 57 MB/s transfer speeds moving large files (on any drive or the RAID array). Now my math says 57 MBytes a second is about 450MBit per second. That's less than half the theoretical speed of GbE (close to the theoretical speed of 5GHz Wireless N, though I know you'll never reach that!). I also know that, in theory, I should be able to hit 125MBytes per second over GbE, a smidge faster than the speed of my drive internally. (It's all SATA 1.5 inside that server, but it's a GbE NAS so, I wouldn't benefit from any faster speeds internally, nor are these 7200RPM drives likely to saturate SATA II or SATA III)
So here's my question;
1) Am I misunderstanding hdparm's readings? Are the drives actually running slower than that?
or;
2) Is there something wrong with my math? Am I misunderstanding how these things convert in the term of bits and bytes?
or
3) Am I having some performance issue somewhere, by which I'm not able to see more than around 500Mbit/s throughput? Is there anything I can do to fix that?
Thanks!
EDIT:
Over wireless N I'm getting a pathetic 14MB/s, if that matters. Not worried about the performance in that spectrum though, whenever I need speed I'm also attached to my 27" LED Cinema Display, and GbE.
Also, to eliminate parts from the equation, I plugged the MBP directly into the Time Capsule and got the same speeds as I got through the switch at my desk. My PC gets the same speeds as well (It's also behind the switch at the desk, the switch connects to the time capsule via a 50ft Cat6 cable)
EDIT 2:
It may also be worth mentioning that I get the same speeds via the Time Capsules internal 2TB drive (right around 57MByte/s)
So someone gave me an old server they were using in their office, and I am using it as a home server. It's an older single core Xeon machine with a 4 port RAID controller, and 4 more Sata 1.5gb/s connections on the MoBo. I have several drives I was using, via USB into my time capsule or even just tossed aside and not used. But this had enough space for me to stick all of my drives in it!
So my question was in regards to speed, and speeding up performance over gigabit ethernet. I'm not working with 4k video or anything else like that, but I am working with a lot of DSLR images so being able to saturate GbE would sure be nice.
Now, maybe my math is all wrong or there is a major concept I'm not understanding, but here's the issue. Internally, most of my drives (I'm running Ubuntu server, so via OS X terminal I SSH into the machine and run hdparm) run around 100MB/s. Currently, I have a RAID 1 array of two of the original drives (80GB) included in the machine, which is for the OS. Then I have a 2TB, 1TB, and 500GB drives mounted inside. The fastest is the 2TB drive, I just ran hdparm and got back a 'buffered disk speed' reading of about 114 MB/s.
Now, via GbE to either my desktop or my MacBook pro (Router is an Apple Time Capsule, which feeds into a GbE switch at my desk that feeds both the desktop and the laptop, router is on the other side of the room directly attached to server, printer, and modem), I get about 57 MB/s transfer speeds moving large files (on any drive or the RAID array). Now my math says 57 MBytes a second is about 450MBit per second. That's less than half the theoretical speed of GbE (close to the theoretical speed of 5GHz Wireless N, though I know you'll never reach that!). I also know that, in theory, I should be able to hit 125MBytes per second over GbE, a smidge faster than the speed of my drive internally. (It's all SATA 1.5 inside that server, but it's a GbE NAS so, I wouldn't benefit from any faster speeds internally, nor are these 7200RPM drives likely to saturate SATA II or SATA III)
So here's my question;
1) Am I misunderstanding hdparm's readings? Are the drives actually running slower than that?
or;
2) Is there something wrong with my math? Am I misunderstanding how these things convert in the term of bits and bytes?
or
3) Am I having some performance issue somewhere, by which I'm not able to see more than around 500Mbit/s throughput? Is there anything I can do to fix that?
Thanks!
EDIT:
Over wireless N I'm getting a pathetic 14MB/s, if that matters. Not worried about the performance in that spectrum though, whenever I need speed I'm also attached to my 27" LED Cinema Display, and GbE.
Also, to eliminate parts from the equation, I plugged the MBP directly into the Time Capsule and got the same speeds as I got through the switch at my desk. My PC gets the same speeds as well (It's also behind the switch at the desk, the switch connects to the time capsule via a 50ft Cat6 cable)
EDIT 2:
It may also be worth mentioning that I get the same speeds via the Time Capsules internal 2TB drive (right around 57MByte/s)
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