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Hybrid Seagate Hard Drive Has Performance Issues
EconolineCrush writes "The launch of Seagate's Momentus XT hard drive was discussed here last week, and for good reason. While not the first hybrid hard drive on the market, the XT is the only one that sheds the Windows ReadyDrive scheme for an OS-independent approach Seagate calls Adaptive Memory. While early coverage of the XT was largely positive, more detailed analysis reveals a number of performance issues, including poor sequential read throughput and an apparent problem with command queuing. In a number of tests, the XT is actually slower than Seagate's year-old Momentus 7200.4, a drive that costs $40 less."
The drives are fine, it's just a firmware issue. They'll fix it in the next few months. It's not like people who bought the drives are screwed because of faulty equipment.
poor sequential read throughput
That's the expected behaviour of this disk. Extremely fast for common tasks (booting and loading apps) and slower for less common and less performance-critical tasks. If you really need the SSD-like performance for all your tasks, buy a 500GB+ SSD, if you have the money for it.
In a number of tests, the XT is actually slower than Seagate's year-old Momentus 7200.4, a drive that costs $40 less.
That's because it's probably a $40 cheaper disk with an $80 SSD attached to it.
This is why I hesitate to be an early adopter of new technology. There's always real-world conditions that occur when a wider sample size comes available (i.e., the Release to Market) than can be reproduced in a lab during testing--and that's true of virtually ANY product. While the problems generally are fixable, it's a pain in the rear to deal with them in the interim. I'll let others be the guinea pigs, thank you very much.
I don't post AC. I like my -1, Flamebaits. Trump/Sheen 2012 on the Batshit Insane ticket!
Quite a common occurrence with hybrids, actually. There are unique difficulties when cross breeding heteroploid organisms, which manifest in.... oh wait.
Does anyone not remember the growing pains of previous technologies? Its not like this has never happened before. $Vendor releases $Product that does not meet $Expectations, charges a premium for it, and then fixes it later. Intel put out a whole slew of processors that couldn't even do proper math!
So, if you're going to live life on the edge of the newest technology, this kind of thing is to be expected. Anybody with higher expectations should stick to last years technology and get the best of *that* instead of the newest $uberware to come out.
Nobodies Prefect
Tidbits for Techs Technology Blog
If there's one thing I've learned with Seagate, it's that they're terrible at fixing firmware issues. Their 500GB hard drives for laptops were notorious for having issues caused by crappy firmware that never got resolved by the time I trashed mine.
The caching and everything is all happening at a level below the OS and the file system, but these tests seem to have all been run in Windows 7 Ultimate x64, whatever that is.
Would another file system (ext4, for example) on Linux/*BSD or HFS+ on Mac OS yield different results, I wonder, w/and w/o swap? Can there be clashing optimization techniques here?
"Just firmware" - don't we remember the fiasco from last year... and their inability to handle it properly.
There was an issue with sound with drives around 2001 that they wouldn't fix. Then Dell said something to the effect of "they think our computers are crap, you fix it or we stop buying from you" and it was fixed. Anything smaller than that, and they would ignore it. I did update the firmware, and it made a huge difference in noise.
Learn to love Alaska
Sadly, this seems to be the case with quality as well.
We buy batches, and my experience has shown a minimum of 10-15% of the drives (seagate) will be defective in some way.
They used to be so damn reliable.
(a.) volatile memory is cheap for the amount needed for only the cache search (all it has to store is maybe 16 bytes per sector which is tiny). The ram cache is a trivial amount of the cost compared to the flash memory which is where your sectors are being stored.
(b.) re-read what I've listed above - I'm not suggesting you remove the OS tier of disk caching.
(c.) a fully associative algorithm is trivial in complexity in contrast to their 'adaptive' algorithms. A CS101 undergrad could implement a reasonable implementation in a hour. This is trivial stuff.
The OS is awful at write-back as if the power fails you've lost state. The benefit of a hybrid drive is that the flash is non-volatile. Writing to the flash ram is cheap. Writing to the disk is expensive. You get the best of both worlds with a flash based write-back cache.
The benefit of flash is it's cheaper than RAM so you can have more of it whilst being far faster than mechanical. Having a 32 or 64 GB flash hybrid drive provides sufficient cache to only rarely need to write back to the disk for most user operations whilst not forcing a 'system' and 'data drive'. As far as the system is concerned, it's just presented as one very fast 2 TB drive (or whatever).
The only time the system will slow down is when you begin to strip the cache which is perfectly reasonable as it means you've exhausted the flash capacity. For 99.999% of usage situations, this will never occur and it will feel just like a very very quick 2 TB flash drive.
I'm curious - what sort of algorithm would you use that can effectively store the data needed for a cache search that can represent 4096 byte sectors in 16 bytes.
As for the 'only time the system will slow down is when you have out-read the cache' - that's exactly the scenario that the OP is describing - massive serial reads on files that are larger than the cache. IIRC the cache was sized on the order of a few Megabytes, and every multimedia file I read all day / all night (music files, video files, gave vobs, etc) is at least that large, most are much larger.
PS - A CS101 undergrad could implement a reasonable implementation in a hour.
Now that's funny. Most first semester CS 101 undergrad students I've met couldn't pour rocks out of a box if the instructions were printed on the underside of the box.
Glonoinha the MebiByte Slayer
Seagate has been crap for awhile now.
You mean like "forever"?
There used to be conner, seagate, and maxtor.
maxtor made 'good' cheap drives.
conner made 'meh' cheap drives
seagate made more expensive 'good drives'. but stopped doing that and started buying other drive companys.
I agree with you about Maxtor, but Conner made SHIT cheap drives. Nothing from Conner Peripherals was ever worth buying. Unfortunately, CP drives were OEM'd due to cost for some time. Seagate has NEVER made "good" drives except for enterprise-class stuff. I grew up in Santa Cruz and so I had a ready supply of used Seagate disks. We used to call them Seizegate because the drives would succumb to stiction constantly. Not a month went by that I didn't have to pull a disk and whack it with a screwdriver to get my system to boot. Once I actually had to pull a cover and manually rotate a spindle it was stuck so hard, and it took significant effort to get it to turn. The same disk burned a trace right off its PCB after that, then I soldered a jumper wire, then it burned off the jumper wire, never hurt anything else in the process but back then computers still contained a bunch of TTL.
(my current fav is hitachi. So long as they dont start making deathstar drives again :P)
That makes me kind of fear them. I just buy WD. So far I've had the best luck with Maxtor and WD over my career.
"You're right," Fisheye says. "I should have set it on 'whip' or 'chop.'"
The SSD is a cache, caches don't do "sequential read"
e.g. Let's read the whole of RAM sequentially see how well your CPU cache performs. Oh, noes! We found a "performance problem"!!!
If all you do switch on, read email, switch off, you'll see a massive boost the next time you do it. Still, better not risk having that because there's an article somewhere on the Internet!
No sig today...
I'd love to buy more memory but I already have 4GB (the limit for many machines.)
Worst case used to be having a WD and a Seagate drive mounted close to each other. The WD killed the Seagate slowly with it's vibrations while the Seagate fought back with heat