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This is a follow up to Server System drive on a USB stick? Good? Bad?.

I set my mind on this 2GB motherboard mountable PATA SSD.

(I already ordered it because I had a voucher, this question is to know whether I can safely rely on it in a server that I don't have direct access and repair work gets expensive.)

It fits in great because i don't have an extra bay for a system drive and a spare PATA onboard. A similar model for 10 pin Motherboard USB would have been an alternative, but as I only have usb 2.0 I chosse this one. Also because I think the PATA connector holds "tigher" and the drive doens't get loose during transportation as likely as USB.

However I have never before dealt with SSDs. In the early stages I only heard of problems with them, but they seem to be good now.

This is a qutoe from the specs:

Specification:
  Size: 61.0mm x 26.9mm x 7.1mm (with housing) 
  Op. Voltage: 3.3V / 5V 
  Op. Temperature: 0C (32F) to 7C (158F) 
  Durability: 10,000 insertion/removal cycles 
  Weight: 11g 
  Humidity: 5% to 95% 
  MTBF: 1,000,000 hours

10,000 insertion/removal cycles means 10,000 times the drives whole capacity? Meaning I can have write activity over 20 TB - right?

MTBF: 1,000,000 hours is something like over a hundret years.

As I don't have any experiences with SSDs I don't know how reliable such numbers are.

I plan to write server logs to a NFS mount but I am not sure yet, but even if I don't and i have a very "normal" server with decent activiy. Do you think there will be any problems?

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The Shurrican
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    The `10,000 insertion/removal cycles` statistic refers to the expected/mean number of times the drive can be physically plugged/unplugged before the drive's PATA connector wears out. – Steven Monday Apr 09 '11 at 15:23

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10,000 insertion/removal cycles means 10,000 times the drives whole capacity? Meaning I can have write activity over 20 TB - right?

Fairly accurate. There are a couple caveats to this, but the biggest one is eliminated by this quote from the spec sheet:

Support Wear-Leveling to extend product life

I'm interpreting that as the controller implementing wear leveling, as opposed to merely permitting it (which really anything does). If that interpretation is incorrect, YMMV.

All that said, it's not clear why you'd select this over a more standard 2.5" or 1.8" consumer-type SSD. Given that you'll spend the difference between this and a such a drive in just an hour or two of remote work, is it really worth it? 1.8" drives, in particular, are bloody tiny, and can be stashed nearly anywhere in a system, or even affixed to the case itself with a bit of work and some small sheet metal screws, since vibration doesn't bother them.

Writing logs externally is generally a good idea, anyway, but if you don't choose to do so, so long as the controller here implements decent wear-leveling, you'll be fine.

One last note: USB 2.0, as an interface, is actually quite a bit faster than PATA (480 vs. a bit over 100 Mbit/s). Some or all of that difference goes away due to other issues, but I certainly wouldn't discount USB offhandedly if you're determined to go this particular route.

BMDan
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  • All my bays are occupied and I dont really want to "tape it somewhere" or drill holes myself or something like that. And I require only about 1 GB or space for my system drive, so cost is a factor. This ones very cheap because of the low capacity. However interesting point with USB. My considerations was not the speed but the load. I think usb doesn't have its own controller and puts load on the systems CPU where PATA usually has its own onboard controller. Or am I wrong? THX about the information about Wear-Leveling, but where did I quote that? – The Shurrican Apr 09 '11 at 13:57
  • USB 2.0 maxes out at 480Mb/s (~57MiB/s), while PATA/UDMA-4 can achieve 66MB/s. So USB 2.0 is not faster than PATA, unless your PATA device is not capable of UDMA mode 4 or better. – Steven Monday Apr 09 '11 at 15:39
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    @Steven: You're absolutely right; I read "Mode 4" on the spec sheet as "PIO Mode 4". Still, from a strict bandwidth perspective, they aren't that far off, which was my original point. @Joe: That quote, complete with typo ("support" instead of "supports") is in the datasheet for the item, linked from Transcend's page: http://www.transcendusa.com/support/dlcenter/datasheet/Datasheet_DOM40V-S_128MB_16GB_%20v1.2.pdf – BMDan Apr 10 '11 at 14:55