Seagate Firmware Performance Differences 177
Derkjan de Haan writes "The Seagate 7200.10 disk was the first generally available desktop drive featuring perpendicular recording for increased data density. This made higher-capacity disks with excellent performance cheaper to produce. Their sequential throughput actually exceeded that of the performance king — the Western Digital Raptor, which runs at 10,000 RPM vs. the more common 7,200 RPM. But reports began to surface on the Net claiming that some 7200.10 disks had much lower performance than other, seemingly identical disks. Attention soon focused on the firmware, designated AAK, in the lower-performing disks. Units with other firmware, AAE or AAC, performed as expected. Careful benchmarks showed very mixed results. The claims found on the Net, however, have been confirmed: the AAK disk does have a much lower throughput rate than the AAE disk. While firmware can tune various aspects of performance it is highly unusual for it to affect sequential throughput. This number is pretty much a 'fact' of the disk, and should not be affected by different firmware."
bug (Score:5, Insightful)
Reliability (Score:5, Insightful)
AAE vs AAK: It's a tie (Score:4, Insightful)
Looks like Seagate designed the new drives for servers (probably file servers) because they're really good a moving large chunks of data around, doing large reads, and large write, but not so good a a ton of little reads and writes. So, don't buy them for your desktop/workstation.
Re:AAE vs AAK: It's a tie (Score:1, Insightful)
Re:Reliability (Score:3, Insightful)
I'd rather hot swap a failed raid drive than bring down a server to increase memory or redesign a solution from scratch in order to achieve the same performance gains. Heck, for the cost of having a coder just look at the I/O intensive code I could have bought another hard drive.
-Rick
Not really same drives (Score:5, Insightful)
A sad detail is that updating an AAK disk to other firmware is impossible, due to physical differences of the two disks.
(emph. mine)
Different disks have different performance. News at 11.
Re:Reliability (Score:3, Insightful)
Re:Not really same drives (Score:5, Insightful)
Re:RAID1 (Score:3, Insightful)
Re:Reliability (Score:5, Insightful)
Your example makes sense, but what if you've already done that? Say your app is SQL-based and does some queries that are O(n^2) complex. You've already spent $20k on a bad-ass server with RAID10, a bunch of spindles, separate transaction log drives, and as much RAM as can fit. Now, a year later, there's more records in the system and performance sucks again. Where do you go from there? These disks don't go to 11. If you want to double the performance of that $20k box, you're likely going to spend not $40k but $200k.
Once you outgrow commodity parts, if you want a 2x speedup, you'll usually have to pay 10x for it. Or wait three years. The price/performance curve is deceptively shallow towards the bottom end.
Re:RAID1 (Score:1, Insightful)
Wouldn't it make more sense and be much easier to run an occasional rsync of tar.gz or equivalent to a second drive for a backup? Taking a drive out of an array and storing it in a bank vault sounds cool but does that really make sense? I mean RAID is great for uptime and availability but it should never be confused with a backup. What about a mouse slip or a virus or an OS glitch or an accidental overwrite of a file? Are you going to be first in line at the bank on the next business day to get that month old disk?
I've got a geek card too but using RAID on an end user PC at home does not seem to make sense to me at all.
Seagates, and Linux HD optimization (Score:4, Insightful)
Also, if you're concerned about Linux block device performance, look at the various kernel tunables. On a single drive, such as those Seagates, I can get extra ~10MB/s. On RAIDs and LVM volumes, the differences can be much higher-- more than twice as fast, in some cases. There are a few parameters that make a difference, and many values you might want to try for each. I have a script iterate through the various permutations, running IOZone on each, so I can see what does best for read vs. write and large vs. small file performance. But I can't release it just yet (employer makes 100% of income from Open Source; employer hates Open Source). Anyway, somebody out there can do better than I, I'm sure :)
This discusses the tunables you'd want to check: http://www.3ware.com/KB/article.aspx?id=11050 [3ware.com]
Note that these do NOT apply only to 3Ware controllers. And the differences in performance can be massive.
Re:RAID1 (Score:5, Insightful)
And many of those are actually slower than a pure, software-only, RAID solution. Sometimes the "hardware RAID" does nothing but offload checksum calculations or other bits onto slower hardware resulting it in being a major performance hinderence rather than a performance boost. Worse yet, if your controller card dies, ALL of your data is now inaccessible. Worse yet again, there is not guarantee future hardware releases, even by the same manufacturer, will be compatible. Heck some of the really low end hardware solutions don't even provide mirrored reads, which should provide a 2x read-only performance boost.
Not all RAID is created equal. And for many, software RAID, especially for Linux users, provides a solution faster than many RAID hardware solutions, is future proof, and only costs a couple of precent in additional CPU load. Best of all, it's free and works well with LVM. In a day and age where multiple cores are common and few actually use more than one, this option doesn't have much of a downside until you're willing to look at *REAL* RAID hardware.
Re:RAID1 (Score:2, Insightful)