[nylug-talk] Paper IT certs and disk drive fabrication differences -- WAS: Slim home server

Wed May 21 22:49:38 EDT 2008

Sorry about the top-posting.  Gmail on BB sucks (I can't even edit the
quoted message to trim it).

What qualifies as a non-degreed engineer?  Can a high school dropout
with a number of years of field experience take an exam to be a PE?

What's the closest one to "software engineering?" ;-)

On 5/21/08, Bryan J. Smith <b.j.smith at ieee.org> wrote:
> On Sat, 2008-05-17 at 18:49 -0400, Chris Knadle wrote:
>> I got an ASEE, then an ASCS [associates in Computer Science], tried being
>> a
>> stockbroker, then after that brief dissappointing job went back to school
>> for
>> a BSEE in "Computer Engineering", which essentially just confuses
>> everybody
>> as to what it is.  It definitely relates to network administration because
>> of
>> the elective classes I've taken.  And after all that I'm still trying to
>> figure out what I want to do "when I grow up".  ;-)
>
> Education doesn't define a person.  Heck, for anyone with 12-16+ years
> of technical experience, the "theory" becomes obvious -- even
> differential and integral calculus and basic transforms.  The 4-5 years
> of "theory" is basically just a juggernaught of "commonality" and
> "lessons learned," and that's why you forget 90% of it.  Because it's
> far more retained when you apply it.  ;)
>
> That's why most State Board of Professional Engineers (BoPEs) allow even
> non-degreed engineers to become PEs, at least in the US (can't say with
> regards to Canada's equivalent), after 12-16+ years experience.  You
> still have to sit the same exams, and the Fundamentals exam may present
> some difficulty without more "academic" study.  But it's still quite
> doable for someone without an ABET accredited BSE to get their PE before
> 35.
>
>> In the job interviews I've gone on so far, my degrees generally don't get
>> discussed and occasionally I wonder if they're even considered.
>
> They _never_ get discussed with the actual technical managers and staff.
> They could care less.  I could care less when I'm hiring as well.
>
> But the HR and procurement departments seem to care.  It's not only why
> the best employees "never get an interview," but even "get lost in the
> process" after an interview.
>
> I've been dropped from consideration more than once because I didn't
> have a CS degree.  I've even had one case where they said they needed a
> "BS in Computer Engineering" verbatim, and they marked me down as an EE
> without the Computer Engineering option (which I have).
>
> I've learned to send just the right info and, sadly enough, 'tude
> towards the HR departments to get them to realize they are f'ing up,
> legally.  Not only for myself, but when I'm trying to hire someone.
>
>>   Uh, well, er...  I don't understand what you're asking.
>
> You said "kind of drive" (sorry, I regurgitated "type" meaning your word
> "kind").
>
>> You're comparing "enterprise" vs "comodity" drives, and everything
>> I've used AFAIK has been "commodity", so I can only compare
>> manufacturers or the interface type: 50-pin or 68-pin SCSI, IDE, SATA.
>
> Neither of which has any influence over reliability.  ;)
>
> Today, vendors outsource left and right.  IBM partnering with Hitachi
> before selling out-right.  Western Digital to Hitachi and Quantum
> (including after Maxtor bought them).  And Seagate finally starting
> outsourcing heavily to Maxtor, although serious drops in QA caused them
> to buy Maxtor.
>
> [ Boeing has run into the same issue first-hand on the 787 Dreamliner.
> And they ended up buying some of the same companies too, especially
> given the "just in time" manufacturing cost savings can cost time. ;) ]
>
> The only thing you can do is ...
>   1)  Find out the model, and how it's fabbed, and
>   2)  Read up on first-hand results with the model
>
>>   And I think all of the drives were
>> 7200 RPM.  There might have been one set of SCSI drives in a mail server
>> that
>> were 10k RPM -- not sure.
>
> Anything 10,000rpm should be 292GB or less.  I could be wrong though.
> Those are of smaller, reduced density platters, and higher costing
> materials.
>
>> Oddly enough -- no.  Most of the servers I personally helped purchase were
>>
>> from vendors that allowed specifying hardware choices.  If standard
>> servers
>> from HP or others were purchased it just so happened that the hardware
>> wasn't
>> used on projects I worked on.
>
> Okay.  So you really haven't.
>
> Understand the whole certification and sample QA on commodity disks --
> near-line/enterprise/RAID/etc... OEM versus consumer/desktop OEM/retail
> is for cost reasons.
>
> If Hitachi, Seagate or Western Digital can sample a lot, and determine
> the drives have reduced vibration and better operational tolerances.
> Doesn't mean they are not going to fail.  It just means over the lot,
> there are less failures.  So when you install dozens in systems, and
> Tier-1 OEMs like Dell, HP, IBM, etc... sell hundreds of the drives in
> dozens of the servers to a single customer, less failures are occurring.
>
> Hitachi, Seagate and Western Digital are not going to warranty disks
> that Dell, HP, IBM, etc... sell in systems that are running 24x7 and are
> not of these samples.  Again, anyone who has been a product manager will
> instantly see the cost differentiation en masse.  They are also far less
> likely to warranty or even charge you a fee if you are sending _many_
> consumer rated discs back to them and the SMART data is coming back as
> operating 24x7, or has other operational data that is well outside
> general, consumer usage.  Not one or two-off, but when you end up
> sending dozens.
>
> That's why the sampling and QA differ.  There is also some added
> firmware that vendors like Western Digital do on buffer flushing on
> their Caviar RE that should only be done on 0 Wait State Caching SRAM
> (capacitor-backed) or buffering DRAM (battery-backed) storage
> controllers.
>
>> Yeah, friends have run into reliability issues on drives that were found
>> to
>> be related to driver firmware.  That's definitely an interesting area.
>
> That's more ATA issues.  The ATA spec is a PITA, and vendors don't
> follow it, making it worse.
>
> ATA is nothing more than dumb traces with two end-points.  Integrated
> Drive Electronics (IDE) on the drive, using Direct Memory Access (DMA)
> mechanisms of the peripheral bus to the system memory.  In between is
> the bus arbitrator, which not only needs its registers to be setup
> proper in the firmware of the system, but handled correctly in the OS
> driver.  Those two things along often conflict, even before we get to
> the system firmware/OS driver v. IDE firmware issues.
>
> The only thing ATA was never, ever designed to do is handle DMA with
> more than one end-point -- i.e., master/slave.  The one thing they did
> right with SATA is not even offer it (finally).  The whole master/slave
> is a left over from the Western Digital trademarked Enhanced IDE (EIDE)
> specification, and it was never supported proper in the ATA spec (only
> recognized for legacy compatibility), and definitely not well considered
> when UltraDMA was offered with DDR and, later, QDR signaling, or CRC
> checking for that matter.
>
> Native Command Queuing (NCQ) has been the latest, horrendous mess.  In
> reality, using an intelligent ATA hardware storage controller (many do
> SAS as well, since SAS is backward compatible with SATA) removes most of
> the bonuses for NCQ.  Many of those cards will also shut down the
> point-to-point NCQ of the ATA bus when they start having issues.  The OS
> never sees it, because the intelligent controller is handling the
> transfers.  It's actually triple over nice because the intelligent ATA
> controller is 1) system memory, 2) bus arbitrator and 3) embedded
> OS/driver in one -- so it removes a lot of factors.
>
> But that's another tangent.  ;)
>
>> Huh; the latest drives I've been purchasing were in the Seagate Barracuda
>> 7200.10 series.  I had not known the were related to the Maxtor line
>> before
>> buying them.  They've been fine so far.
>
> The Seagate Barracuda 7200.10 line (187GB/platter flagship,
> 250GB/platter in 250GB form) is probably their best model since the
> 7200.7 (100MB/platter flagship).  The Maxtor drives of the same capacity
> are actually fabbed as 7200.10 drives by Seagate, under their QA
> control.  ;)
>
> The new 7200.11 line (250GB/platter flagship, 320GB/platter in 320GB
> form) is having serious issues with firmware.  It's something to be
> avoided right now until the kinks are worked out.  Seagate isn't the
> only one having issues, Hitachi and Western Digital are as well.
>
>>    Last I worked directly for an I.T. department at a company they
>> considered
>> all hard disks to be equal (obviously a simplistic conclusion) and had no
>> interest in having anyone research drive relibility, method of
>> manufacture,
>> etc.  "Just get the box a disk" was essentially the bottom line.  [I would
>>
>> have much prefered more design thought to go into hardware purchases, but
>> hardware purchases were usually done in a rush for several reasons.  :-(]
>>    And since then I still use commodity hardware for stuff I build for
>> myself,
>> and if I work on client's servers I don't carefully examine what type of
>> drive a box has -- I haven't been asked to examine that.  Etc.
>
> My life is heavily CYA, especially since I work for a vendor myself.
>
> I have more recently been in the middle of an Intel debacle, and their
> utterly lack of full disclosure (even to us vendors under NDA) with
> regardless to Machine Check Exception (MCE) issues -- specifically, as
> you can find in public documentation now -- the TLB.  Yes, TLB.  AMD
> isn't alone.  ;)
>
> Made me completely appreciate AMD's decision to withhold their Processor
> 10h (Barcelona) Stepping B2 multi-socket (Opteron) processors until they
> worked out all the TLB issues on the B3.  Intel shipped G0 steppings on
> not just their uni-socket Core 2s, but their multi-socket Xeons.  I was
> hitting the Intel microcode dat file for Linux weekly for some time
> there.  ;)
>
> Can't say more than is public, being under NDA and all.
>
> Likewise, because SAS is the mature SCSI-2 protocol using the same SATA
> PHY (although externally SAS is a crapload better, mechanical/electrical
> than eSATA, but that's another story), a lot of enterprise go the SAS
> route instead of SATA when they hit non-commodity material/fabbed
> 10-15,000rpm drives.  After all, the cost of the added SAS firmware
> isn't the biggest cost, but the materials/fab required for the spindle
> of the drive.
>
> But SAS, just like SCSI or FC, has nothing to do with the reliability of
> the drive mechanics itself.  It's more of the non-commodity pairing of
> cost in fab with cost in firmware.
>
>
>
> --
> Bryan J  Smith              Professional, Technical Annoyance
> mailto:b.j.smith at ieee.org  http://www.linkedin.com/in/bjsmith
> -------------------------------------------------------------
>            Fission Power:  An Inconvenient Solution
>
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