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Faulty Marvell Chips Delay SATA 6G Launch
Vigile writes "The SATA 6G standard offers more than simply a faster 6.0 Gb/s data throughput speed, to wit: improved NCQ support, better power management, and a new connector to support 1.8-inch drives. While modern-day, spindle-based hard drives struggle to keep up with SATA 3G speeds, modern SSDs are nearly saturating the existing standard, and a move to SATA 6G was welcome in the hardware community. It looks like that technology will be delayed, though. The only chip supporting the standard today, the Marvell 88SE9123, is having major issues. Motherboard vendors including ASUS and Gigabyte, which had planned on releasing SATA 6G technology using the chip on Intel Lynnfield platform motherboards later this summer, are having to remove the Marvell 88SE9123 and redesign their boards at the last minute due to significant speed and reliability issues."
... "modern SSDs are nearly saturating the existing standard" ...
æeee!
Faulty Marvell Chips...
Maybe they should stick to comic books.
When our name is on the back of your car, we're behind you all the way!
>> The only information we have gotten from anyone revolves around some hardware AND software issues that are preventing the SATA 6G speeds from actually reaching 6.0 Gb/s
Instead of delaying the launch, they could just rename the chip. SATA 5.5G for example.
Joke detection fail.
DISCLAIMER: I am very rarely serious. If the above comment seems asinine makes no sense, it is most likely a bad joke.
Even the 6G standard won't hold for high-end SSDs (which seem to be raid striped in one unit, AFAIK). The long-term solution for those are ones that connect via PCIe, so this doesn't seem to be that big a deal, really.
Intel's X25-M seems to perform 200 MB/s constant throughput. Granted that's "only" 2/3rds of the 3 Gbps that SATA 2 delievers, but the quote was "nearly saturate".
And if we're already at 2/3rds, that's a fairly compelling argument to upgrading. On laptops it can become an issue much quicker, as you usually only have 1 eSATA port, and port multipliers do not increase bandwidth. Hooking two X25-Ms onto a single eSATA 2 port can saturate it while doing non-random transfers easily but still have room left over on eSATA 3.
But if we're merely talking SSD in general, we can always point to Fusion-io ioDrive which bottoms out at 429 MB/s.
*cough*Regular mints are better if it's just a cough. No point in taking allergy medicine if you aren't allergic.
Take a long hard think about this.
What manufacturer is going to make SATA SSD's that can saturate the fastest SATA port?
Sounds to me like a bad idea. Surely there are some tradeoffs between speed and some other also important metric. Ex, faster might mean larger erase block sizes.
It is likely that Intel could have made their product much faster, but without any benefit at all to doing so, they wouldn't.
This new SATA, while important, it sort of too-little-too-late. We need a much higher ceiling, and we need it yesterday.
"His name was James Damore."
Most sequential throughput benches hit the drive with sequential requests, and are not multithreaded. You end up seeing throughput lower than the theoretical interface bandwidth because of the latency involved for each request. A queue depth of 2 or 4 will give an X25 enough heads up to truly saturate the bus. I've recorded as high as 285 MB/sec from an X25-M using an NCQ-capable benchmarking tool.
Also, don't forget SATA uses 8/10b encoding, so you have to account for that overhead as well when calculating theoretical maximum throughput. Doing the math, you'll find 285 comes to 95% of a 3 GB/sec SATA interface. That's way higher than 200 MB/sec and close enough to call saturated.
Allyn Malventano
Storage Editor, PC Perspective
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Honestly, Marvell chips have cost me more grief on Linux installs than all other vendors combined. If this gets mobo vendors to design out Marvell, then I say: "Grand!".