Hybrid Seagate Hard Drive Has Performance Issues 67
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."
expected behaviour (Score:4, Interesting)
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.
Re:Well (Score:5, Interesting)
OS and file system agnostic? (Score:5, Interesting)
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?
Re:Well (Score:5, Interesting)
Re:expected behaviour (Score:3, Interesting)
Hybrid drives aren't made to be first choice. They're made to be an affordable choice. If you want to assemble an affordable but fast PC nowadays, you'll probably end up with a 40GB SSD for OS+Apps with a cheap, silent and big hard disk for storage. The problem with this approach is the barrier at 40GB. What if your SSD needs more space? What if it turns out that some frequently-used data is on the hard disk? Or that 60% of the OS files are hardly used? Hybrid drives try to decide for themselves which data should be optimized.
But I'm not really sure that they're optimizing at the right level. Maybe they should expose themselves to the operating system as two separate partitions and let the filesystem implement the optimization while showing up as one single volume to the end-user.
Re:Well (Score:3, Interesting)
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.
There's nothing to "fix" (Score:3, Interesting)
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!