[ale] Linux alternative recommendation ?

Tue Oct 25 10:01:36 EDT 2011

Ron,

Much gratitude for stayin' with me on this, and the summary as well.

C.Thomas

On 10/24/2011 5:05 PM, Ron Frazier wrote:
> <disclaimer ON>
>
> I'll be glad to give you my opinion.  Opinions are plentiful and 
> cheap.  Your mileage may vary.
>
> I am not a physicist, and am not an expert on flash memory technology.
>
> <disclaimer OFF>
>
> OK.  An SSD is a giant version of a memory stick, more or less.  The 
> same pros and cons as mentioned before apply.  I cannot speak to the 
> susceptibility to airport screening equipment as mentioned in my other 
> post.  I love the idea of an SSD, although I don't currently own one.  
> Properly configured and properly supported by the operating system, 
> they are blazing fast.  One big current problem is cost, so you have 
> to determine if it's worth $ 2 / GB to get one, as opposed to $ 0.10 / 
> GB for HDD.  As someone else said, you probably won't get much speed 
> advantage over an external HDD when connected to a USB v2 port.  
> According to Wikipedia, USB v2 is capable of 480 Mbit/s (60 MB/s).  
> That's the most you'll get out of any device connected to a USB v2 
> port.  The SATA port on either a HDD or SSD is capable of about 6X 
> that speed.  So, the bottleneck is going to be the USB port.  I don't 
> know for certain, but I suspect that either the SSD or HDD will 
> perform similarly when connected to a USB v2 port.  The HDD will be 
> faster, and the SSD will be WAY faster, when connected to an internal 
> SATA port on the PC.
>
> I tried an experiment by copying 20 Ubuntu ISO files (about 13 GB) 
> from one internal 7200 RPM SATA drive to another in my PC.  Data 
> transfer speed varied widely, which may be due to the two platters not 
> being synchronized.  In any case, the max consistent speed was about 
> 50 MB / sec.  So, I don't know if a 7200 RPM drive can max out a USB 
> v2 connection, but it will come close.  A 10,000 RPM drive could 
> probably exceed the limits of a USB v2 connection.  They are available 
> in 2.5", but cost a bit more..  An SSD will almost certainly max out 
> the USB v2 connection.
>
> So, the bottom line is this.  The SSD is probably better for your use 
> as an external drive IF A) you want to pony up the money, and B) you 
> convince yourself that airport scanners won't fry it.  It won't be 
> much faster than a HDD if on USB, but it will be very durable and 
> pretty much immune to mechanical shock (don't run over it with a big 
> truck).  It will be mostly immune to electrical shock if properly 
> enclosed (don't intentionally make sparks to it).  Get one with a 5 
> year + warranty.
>
> If you're convinced that airport scanners will fry flash memory, go 
> with a g-shock protected (as someone mentioned) NON HYBRID HDD with 
> 7200 RPM speed.  If you want maximum possible speed, go with 10,000 
> RPM.  I didn't think about the airport thing when I originally 
> mentioned the hybrid drive.  For that matter, I don't know how airport 
> scanners effect HDD's either, but I presume, not so much.  The HDD 
> will still be more susceptible to mechanical damage than an SSD, so 
> g-shock feature notwithstanding, try not to smack the drive, 
> especially while it's running.  Again, get one with a 5 year + warranty.
>
> As I mentioned in another post, I have misgivings about the long term 
> reliability of any flash memory device, including SSD's.  No matter 
> what you choose, you need regular backups of critical data.  Perhaps 
> even more so with a flash memory device.  Over the last few years, 
> I've observed failures in several types of flash memory devices as 
> follows:
>
> a) when I was teaching, students reporting that their files vanished 
> or were not accessible on memory sticks
> b) my own relative's inability to access photos on a memory card, 
> which I had to recover
> c) a GPS device that suddenly decided it didn't want to run it's 
> program properly, and didn't want to take a firmware update
> d) routers that, periodically, start getting flaky, and have to have 
> their firmware reloaded
> e) some may call me crazy for mentioning this, but, severe solar 
> storms are predicted in 2012 and beyond, which MAY be more likely to 
> disrupt flash devices (I'm not an astronomer either.)
>
> All these devices (a - d) are flash memory based.  And, I've seen them 
> all flake out.  I wouldn't probably want to backup an SSD to an SSD.  
> I'd back it up to an HDD, and possibly to online backup too.
>
> So, there you have it, long answer to short question.  As with many 
> things in technology, the answer is "it depends" on your use case.
>
> Hope it helps.
>
> Sincerely,
>
> Ron
>
>
>
> On 10/24/2011 3:14 PM, Courtney Thomas wrote:
>> Ron,
>>
>> What is your take on SSDs vs HDDs ?
>>
>> Thanks again,
>>
>> C.Thomas
>>
>> On 10/24/2011 1:47 PM, Ron Frazier wrote:
>>> There are a couple of benefits to "rolling your own" external 
>>> drive.  It is frequently the case that the prefab drive in a case 
>>> type of packages don't have adequate cooling.  While the compact DIY 
>>> enclosures for 2.5" drives usually don't have fans inside, good ones 
>>> are made of aluminum, which has good heat dissipation.  Bigger 
>>> enclosures sometimes have fans.  Western Digital had problems a few 
>>> years ago with their packaged drive in a case (my book, passbook, 
>>> whatever it's called).  The drives would fry themselves to death.  
>>> Then you have to fret with RMAing the thing.  If you open the case, 
>>> you void the warranty, and I don't think they had a 5 year 
>>> warranty.  If you choose carefully, you can get a bare HDD with a 5 
>>> year warranty.  Then you can switch it in and out of cases as you 
>>> see fit.  You can also upgrade it to a larger drive if you choose, 
>>> and not worry about voiding the warranty.
>>>
>>> Sincerely,
>>>
>>> Ron
>
> <snip>
>
> -- 
>
> (PS - If you email me and don't get a quick response, you might want to
> call on the phone.  I get about 300 emails per day from alternate energy
> mailing lists and such.  I don't always see new messages very quickly.)
>
> Ron Frazier
>
> 770-205-9422 (O)   Leave a message.
> linuxdude AT c3energy.com
>
>
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