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1  Hardware and U-Boot firmware / Hardware / Re: I just received a new Dreamplug today on: March 29, 2011, 06:03:41 AM
NO commonly-used benchmark should be relied upon as a benchmark. However, there should be a way to compare apples-to apples in  meaningful way.

It occurs to me that underclocking would be a relatively easy way to limit the speed (and therefore the heat output) of these devices, have you asked Marvell or GST whether the SOC is underclocked?

This guy used the old nbench benchmark program and got interesting results, you might could repeat his experiment on your plug(s) for comparison.

And MySQL has a benchmark suite, which he also uses.

Try one or both of these and let us know your results!
2  General Category / General Discussion / Re: Plug vs Nettop on: January 29, 2011, 10:32:38 AM
I'm not sure you could convert movies on the SheevaPlug at all.

1200 MHz sounds fast compared to a CPU that runs at 300, 500, 800 MHz, and it is, but ARM CPUs are far slower than a Pentium of the same clock speed for any purpose that involves floating-point arithmetic. 

For comparison, this benchmark measured the floating-point performance of the original SheevaPlug as 35 times slower than a 1.2 GHz pentum M and 86 times slower than a 2.4Ghz Core2Duo. In other words, it might take the SheevaPlug between a day and a half to four days at 100% utilization to transcode the same video that the Pentium M could do in a couple hours or the Core2Duo in real time.

ARM CPUs are frequently designed without the circuitry for floating-point arithmetic, and that's part of the reason they deliver such good performance at such low power. When they encounter a calculation that requires floating-point, they have to run a short machine language program to find the answer rather than execute a single instruction in hardware, and that takes much more time to do.

If floating-point performance is a design consideration, some ARM CPUs have onboard floating-point, some can be outfitted with floating-point coprocessors, and sometimes specialized hardware like a Graphics Processing Unit can be used to handle the heavy lifting on the CPU's behalf. 

You would be well-advised NOT to buy a Plug Computer for any sort of media transcoding because there are probably mobile phones better equipped for that kind of work than the SheevaPlug. I doubt you could run any OS other than Linux under virtualization for similar reasons, though you wouldn't need to (Linux chroot can load and run a 'guest kernel' that would let you run Slackware under Debian if you chose, so Linux virtualization under Linux seems pointless.)

I haven't decided if or when to dispose of my Plug(s). I've heard that grafting a 5V/2A AC adapter onto the plug works better than the original PSU, but if I do sell them I would prefer they went to someone who understands the PSU could fail at any time, a replacement part could take weeks or months to obtain, and might need to be replaced again ten or twelve months hence. I'll send you a PM when I know what I plan to do.
3  General Category / General Discussion / Re: Plug vs Nettop on: January 28, 2011, 12:11:00 PM

The eSATA Sheevaplug is substantially identical to the original except it has an eSATA connector and a version of uBoot capable of booting from an attached drive (the GuruPlug could only be booted from NAND or USB).

When the SheevaPlug was introduced back in 2009, it occurred to everyone that the device was just an eSATA port shy of being the best NAS controller EVAR. One guy actually installed his own eSATA port from the circuit-board up, you can read about it in the Hardware forum if you're interested in how he did it.

GST started manufacturing an eSATA version of the plug, but made resale arrangements only with CTERA (who essentially took it off the market by selling it only in conjunction with its own services) and NewIT in England, who distributes it throughout Europe (and cheerfully exports it back to the USA, where savvy Americanos can pick it up in a snazzy black case if they choose to buy it from overseas).

What the eSATA port buys you is disk performance. USB performance is somewhere between severely deteriorated and crippled when you have multiple datastreams crossing the pipe (like a backup running at the same time a movie is streaming). The Sheeva's CPU has to drive that interface, so the processor works very hard to manage the connection. eSATA runs very fast, almost the same speed as an internal SATA connection, and works well even given multiple or bidirectional streams and without overloading the processor to do so.

I'm not handy enough to install my own eSATA port, but when the GuruPlug came out it had an eSATA (plus all the other stuff) for about the same cost as reimporting an eSATA Sheeva from the U.K., so I went with it. I had the perpetual reboot variation of the heat problem, and notified GST of my intention to return it right away. I  explained that all I really cared about was the eSATA port, the rest was just gravy, and if they could see their way clear to sending me one of those I'd consider it an even exchange.

They did, I did, and all was well until my original SheevaPlug lost its power supply several weeks later. My eSATA plug still runs like a champ, but I don't anticipate the power supply living out the year, and I won't be easily able to afford a replacement when I suspect it's likely to blow.


What the Plug Computer is really good at is providing the services of a Network File and Print Server:

* Secure access to your LAN while away from home via the Internet (and/or through a web browser via a firewall),
* Linking private LANs together via the Internet,
* Internet traffic caching and filtering, to improve the performance and security of your LAN,
* Running a private web or mail server,
* Operating or monitoring security cameras,
* Providing, securing and sharing data between family members (public and private directories),
* Centralized and/or RAID-backed storage of your family's computer data,
* Streaming audio and video files to devices that are equipped to play them back,
* Operating a VoIP phone system ...

Those sorts of things. Of course any computer running Linux can do the same, but the Plug computer is (supposed to be) small, cheap, and reliable enough to run unattended on a 24x7 basis.

What the Plug Computer is NOT good at is creating or processing graphics, audio and video files, because it has no graphics coprocessor or floating point unit but multimedia requires a great deal of that kind of number-crunching.

In regards to your WLAN question, a USB WiFi dongle will generate less heat, and what heat it does generate will be dissipated outside the case, but it will put a load on the CPU which will generate heat in itself. Pick your poison.

if I buy a Zotac, I'm buying it to replace my eSATA SheevaPlug. If it's fast enough to play back video (I'll be using Linux exclusively, which has far lower overhead than Windows) that's a big fat bonus, but I already have a MythTV/XBMC/HTPC (the aforementioned Everex gPC Mini), I just want a NAS controller that I don't have to replace on an annual basis.

And no, PSUs draw their wattage in proportion to their load. A 700-watt PSU should draw very little power when idle, but quite a lot when it's transcooding a DVD to H.263 for playback on an iPod. Smiley
4  General Category / General Discussion / Re: Plug vs Nettop on: January 28, 2011, 10:17:48 AM
There's a problem in game theory called the 'sunk cost dillemma' which explores the problem of why people won't abandon something they've put considerable personal investment in, even if they would come out far ahead to simply cut their losses and move on.

I'm on my third Plug Computer now: the first was a USB model that died of a bad PSU, the second was the notorious GuruPlug Server Plus which I returned before the warranty window expired, and the third is an eSATA model graciously provided by GST in exchange for said GuruPlug (and has been humming along very nicely until its own PSU dies, which I expect sometime before the end of 2011).

The Plug Computer has one proven use case: because it's so small, so low-powered, and so complete in its Linux capability, it makes a good NAS controller, very much better than almost any entry-to-midrange consumer NAS. (In fact, I bought my first SheevaPlug to replace a Synology DiskStation which had the same CPU, far less RAM and Flash, and no freedom to customize or replace the firmware).

I've grown very fond of having a NAS, but I'm concerned that my SheevaPlug won't live out the year, and I predict it will conk out between Halloween and Christmas, just when any disposable income I might have will be earmarked for other things. I'd be wise to make plans to replace it now, but with what?

  • I have an Everex gPC Mini that could handily take over for the SheevaPlug except that it lacks eSATA, and therefore needs an external controller of some kind to talk to my RAID Enclosure. I could buy yet another SheevaPlug or at least a replacement PSU, but that would only postpone the decision for another year, or until they stop making spare PSUs or the SheevaPlug Classic itself.

  • I could order a DreamPlug and possibly repeat the GuruPlug debacle, but that's the sunk cost dilemma talking. Even if the dreamplug works exactly as advertised, it just reinforces my commitment to subsidizing a failed platform. In any case, the plug Computer has ceased to be even a relatively cheap option this time around. At $99 or even $129 it was worth considering, but at $179 plus delivery? That puts it in direct competition with nettops that it pales in comparison to.

  • Finally, I could buy a nettop like the Zotac ZBOXSD-ID10-U or better yet the ZBOX-HD-AD01. At this point I need only a NAS controller, so one of these plus a $20 2gb SODIMM should cost the same or less as a DreamPlug, be delivered in days rather than months, and be warranted to last a year at minimum.



5  General Category / General Discussion / Re: DreamPlug on: January 27, 2011, 08:55:50 AM
It depends upon the perspective, doesn't it?  Sure might seem like a rip-off to package the JTAG separately if you only plan to buy one unit.

It's a rip-off to package the JTAG separately if that's the only way to recover the device from brickville.

Quote
But, maybe if you've got something to sell to the public, you buy 100 Plugs and one JTAG port.  That way, you don't have to pay for the FDDI chips, etc. for all the sale units.

That's really poor strategic thinking. Field upgrades are impossible without the FDDI chip. Your customers can't just tether it to their PC and use their AmahiTunes Poseurware to synchronize, reflash or extend the plug's firmware, they would have to ship the whole unit back to you. Or you could send them an updated MicroSD and dare them to violate their warranty by opening the case and atempting to replace it themselves (unless you also intend to turn your back on your customers after their worthless 30-day warranty expires, just like GST did to you), or introduce your customers to GST's exciting new Disposable Computing concept where they simply throw away their old plug computer and buy a new one every year (or after every power supply burnout, whichever come first).

Has it occurred to you that even the cable of the GuruPlug JTAG board was coincidentally designed to break or wear out after just a few insertion/removal cycles? You'll need well more than just one of them to flash your hypothetical 100 Plugs, and since the cables aren't sold separately from the JTAG board they have an effective replacement cost of $30. You'd be better off buying 100 JTAG boards and shipping those in the box (along with a note of apology for the shoddy design, construction and workmanship of your products) to your customers.
6  General Category / General Discussion / Re: DreamPlug on: January 26, 2011, 06:12:15 PM
Okay, Peter, I tried reasoning with you, now you're just being obtuse.

7  General Category / General Discussion / Re: DreamPlug on: January 26, 2011, 04:04:51 PM
It`s chicken and the egg !!! you need uboot or software to make it use the sd-card.

Okay, I'll buy that. But it doesn't alter the big picture, which is that the FTDI chip SHOULD be on the system board, as with the SheevaPlug. Putting it in an external case and charging $35 for it is a ripoff.

8  General Category / General Discussion / Re: DreamPlug on: January 26, 2011, 02:46:25 PM
]The NOR Flash is the boot strip , need for the first step to do anything .

I'm not saying you don't need uBoot (or Redboot or similar) to boot the thing, I'm saying there's nothing magical about NOR/NAND that requires you to load uBoot from there. It would work just as well from the SD card containing the kernel and rootfs.

I believe the design is gimped to make the Low cost dedicated JTAG tool anything BUT an optional accessory. Get it?


9  General Category / General Discussion / Re: DreamPlug on: January 26, 2011, 12:24:16 PM
Now Playing: Won't Get Fooled Again by The Who

Let's take a look at that datasheet again while wearing our bullshit-sensitive sunglasses:

  • Boot device: 2MB SPI NOR Flash for uboot
  • Flash memory: 1GB on board micro-SD for kernel and root file system

    Verrry interesting. Why do we need the NOR at all when we have a spacious MicroSD to hold the device's firmware?

    Anyone? Anyone? Bueller?

    That's right! because if you had uBoot living on MicroSD you wouldn't need to buy a separate JTAG device to flash it with!

  • 2x Gigabit Ethernet 10/100/1000 Mbps
  • 2x USB 2.0
  • 16-bit ADC/ DAC
  • WiFi : 802.11 b/g
  • Bluetooth: BT2.1 + EDR

    No fan? No obvious means of adequate ventilation? Even without the PSU on board, just how many cubic feet per minute get sucked through those little slots on the case?

  • Low cost dedicated JTAG tools for system development

    Goodness! Will the system be backed by GST's ironclad 30-day warranty, too ? 


I'll pass, but thanks for trying.
10  General Category / General Discussion / Re: Updating sheevaplug software on: January 26, 2011, 12:23:13 PM
Now Playing: Won't Get Fooled Again by The Who

Let's take a look at that datasheet again while wearing our bullshit-sensitive sunglasses:

  • Boot device: 2MB SPI NOR Flash for uboot
  • Flash memory: 1GB on board micro-SD for kernel and root file system

    Verrry interesting. Why do we need the NOR at all when we have a spacious MicroSD to hold the device's firmware?

    Anyone? Anyone? Bueller?

    That's right! because if you had uBoot living on MicroSD you wouldn't need to buy a separate JTAG device to flash it with!

  • 2x Gigabit Ethernet 10/100/1000 Mbps
  • 2x USB 2.0
  • 16-bit ADC/ DAC
  • WiFi : 802.11 b/g
  • Bluetooth: BT2.1 + EDR

    No fan? No obvious means of adequate ventilation? Even without the PSU on board, just how many cubic feet per minute get sucked through those little slots on the case?

  • Low cost dedicated JTAG tools for system development

    Goodness! Will the system be backed by GST's ironclad 30-day warranty, too ? 


I'll pass, but thanks for trying.
11  General Category / Application ideas and development Q/A / Re: GlobalScale, you have some MAJOR explaining to do. on: January 14, 2011, 03:15:43 PM
Don't you guys know what a HOSTS file is?

A HOSTS file maps names to IP numbers in the absence of a DNS server. In the above case it makes sure that the computer can always lookup the IP address 91.189.88.36 given the hostname ports.ubuntu.com even if the computer is offline or only intermittently attached to the Internet (as in an installation or upgrade scenario).

One of the most common applications of a HOSTS file is to provide name resolution for internal networks (e.g. myrouter.my.network --> 192.168.1.1, mypc.my.network --> 192.168.1.6, and so forth). So long as the HOSTS file is copied to all machines on your side of the router, they can find and communicate with each other by name and without the trouble of setting up a private DNS server for internal queries. You can also put vital mappings in your HOSTS file like your ISP provider's DNS, mail, time and other servers to provide some functionality in the event of an upstream outage.

Now, I believe Marvell and the Plug Partners (now there's a band name for you) deserve criticism for the apparent collapse of the 'plug ecosystem' as it were, but the HOSTS file and its function is a bloody elementary component of the TCP/IP protocol, gentlemen. It's not their fault you evidently have no clue what you're looking at.
 
12  Hardware and U-Boot firmware / U-Boot stuff / Re: plug with only green led on and no serial connection...I need a resurrection on: October 21, 2010, 07:55:08 AM
Sounds like a dead power supply to me.

My SheevaPlug's PS died after about a year of use (aug 2009 - jul 2010) .

I haven't ordered a replacement PS yet because I still have one working plug, but when I do I'll buy 2 on the assumption that the other plug's PS will fail sooner or later.

13  General Category / General Discussion / Re: Newbie questions - I need a low power computer.... on: September 08, 2010, 05:56:29 AM
Actually you have at least one other option:

5. Buy a commercial single or dual-drive NAS (~£130, more or less depending on brand, number of installed drives and features/performance).

The SheevaPlug is splendid at its best, but be aware of its drawbacks/limitations:

1.  People  have reported mixed results using multiple hub-attached USB drives. Generally you can't boot from such a configuration, but you should be able to access them if you boot from Flash/SDHC.

2. Flaky power supply. I have one plug that died after 13 months (and I consider myself lucky that it lasted that long). Replacement power supplies are available for the time being, and many people have managed to rig up a connection to an external AC adapter, but if you buy a SheevaPlug you should do so on the assumption that the power supply WILL sooner or later fail.

3. USB performance (in general) is very poor, particularly in the presence of multiple/bidirectional IO streams. Do give the eSATA Sheeva serious consideration (paired with an external RAID enclosure it's a very nice do-it-yourself NAS,  power supply issues notwithstanding).

4.  Reconcile yourself to Debian (or one of the several other Linux distros avialable for the Plug), as Ubuntu is no longer developed for the version of the ARM processor in the Sheeva.


If I had to do it all over again, I'd choose an Atom/Ion board and a Mini-ITX NAS case. The SheevaPlug's package size, power savings and hardware limitations just aren't worth the hassle to me anymore.
Quote
14  Linux Stuff / Linux distributions / Re: how to preserve flash disk on: August 15, 2010, 08:27:00 AM
If you have better solution to preserve the flash disk, I'm ready to listen it.

Très simple: use flash for the purpose of storing a kernel/initrd but put your rootfs on a more suitable (or at least less fragile) device such as a USB stick, SD card or external HDD.

In principle, the whole system can be booted and run off the network with NO flash involvement apart from executing u-Boot.

Blüto l'American





15  Linux Stuff / General Linux questions / Re: Mounting eSATA Drive on boot on: August 15, 2010, 06:05:38 AM
I'm a proud owner of a black eSATA SheevaPlug with Debian 6.0 Squeeze on a 8GB SD Card.

Same problem what to do??

First, you should seek assistance with this problem from NewIT. eSATA SheevaPlugs are hard to come by in the U.S., but even if they weren't, we can only speculate about the layout of the card, the contents of your u-Boot environment and what changes may have been made to the 6.0 (unstable) branch of Debian since the SD card was manufactured.
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