What transfer speeds to esata external drive?

Does anyone have an external drive connected via esata, ideally to a XPS 1645 but if not any other XPS 16 will do, and if so what sort of transfer speeds do you get?

I ask as I need to sort out some external storage and I was all set to get a small cheap NAS such as a Netgear Readynas Duo but from the reading I've done the transfer speeds seem pretty low even when using a gigabit network (around 24 MB/s reading and less than that writing).

I'm just wondering whether an esata drive would be faster instead although it'll be yet another thing to have to plug in.

 

Most NAS devices are pretty crappy in terms of bandwidth. Building your own NAS with quality parts might be expensive, but you'll get better results too.

As for eSATA, you will get native hard drive speeds.

 

Until I started looking into it in more depth I didn't realise just how slow most of the NAS devices were.

If esata gives speeds as good as plugging an extra drive inside the laptop then that's is probably the cheapest and easiest method to use although I do lose the other perks of a NAS.

I suppose thinking about it a Gigabit NAS is never going to be as quick as an esata device when you look at the speeds of the interface and the extra overheads involved in running a NAS.

Do you know what throughput can be achieved with a decent, but not too expensive NAS? In an ideal world I think I could do with getting around 70MB/s upwards.

 

Are you going with regular IP protocols (NFS, CIFS/SMB, etc)? If so, I'd be very surprised to see that high. It's just a factor of all negotiation overhead. Now, using iSCSI with jumbo frames? Now you're talking. But really, you need to ask yourself how much speed to you need and how often you will run into the limit. I use my eSATA port for doing Acronis backup jobs to a 1.5TB drive, and since it's sitting at 1.5Gbps (SATA I speeds) I get around the speed you're talking or a bit better. But that's it. Now, if you actually track how much I/O is going through the system at that moment, you'll see maybe twice that and you're saturating the hardware, but not "seeing" it because the little graphic is telling you only 50, 60, or 70MB/s. Something to think about.

 

Gigabit ethernet is simply that ... 1000 Mb/s or about 125 MB/s (1000/8). Of course you won't get that due to overhead. Considering most drives peak at around 90 MB/s, you "should" be okay ... unless you have SSD drives then you will not see the benefits of SSD as SSDs are what ... 150MB/s and up.

eSATA is 3000Mb/s or about 375MB/s minus your overhead. eSATA would definitely be faster. eSATA would obviously be best for SSD drives.

If you plan on accessing your NAS via wireless, your wireless becomes the bottleneck, even if the router has gigabit ports. Even at N speeds you are currently limited to 300Mbs or 37.5MB/s minus your overhead.

You will get much better performance with a NAS directly wired (either by network, eSATA, or even USB2) versus wireless.

 

I'm currently using a desktop PC and transfer the work to a laptop when I need to go out on site. Maintaining two machines with everything I need is annoying me and as both machines are getting a bit long in the tooth the idea is to replace both of them with a decent laptop hence ordering an XPS 1645.

I've ordered the laptop with an SSD but I could do with some extra storage space (about 1TB should do) that'll be used reasonably frequently when the laptop is at a desk and ideally I'd also like this data to be mirrored using RAID in case of hdd failure.

Ideally I'll spend the bulk of the time working with files on the SSD but I know that I'll have to access files on the external storage that are a few GB reasonably frequently and I obviously want to keep the access times down as low as possible.

Based on my current use I think that I'm going to find 25MB/s annoying and too slow so I was hoping to treble that kind of speed if possible.

I'll be running using a wired gigabit connection most of time and a NAS would make life easiest as with an ethernet connection it's one less thing to connect when the laptop is taken to and from the desk.

When the laptop arrives I'll test my network speed while it's connected to another machine on the network and I suppose that'll give me the maximum throughput I'll be able to achieve with a NAS.

Once I know this I'll be able to decide whether a NAS may suffice or whether I need to look at eSATA for faster speeds.


Also on a related note as the laptop will spend a large proportion of it's life as a desktop replacement it's going to have a number of things connected to it including two monitors, ethernet, keyboard, mouse, and possibly eSATA.

I know there is no proper docking station for the XPS however can anyone recommend a decent one, perhaps using expresscard to get good bandwidth, that'll allow me to connect things as easily as possible?