I just want to point out that although seller seems to have lots of feedback. There is no other items he is selling. I'm just a little suspicious. FYI.Just in case anyone has interest, saw this yesterday. Not far off from same pricing structure for 2x's the device space.
HGST Ultrastar SSD800MM HUSMM8080ASS200 800GB Internal 2.5" (0B28658) SSD | eBay
hmm...i see a bunch of other items in that seller's store?I just want to point out that although seller seems to have lots of feedback. There is no other items he is selling. I'm just a little suspicious. FYI.
Have you tried striping just two drives? What slot is the HBA in? You might be running into slot bandwidth limitations.I have these striped in Server 2016 just to eval the performance and I'm not getting the read performance I would expect based on the spec sheet. 3376 MB/s for 4 drives that claim 1100 MB/s read per drive, so I'd think I'd be seeing 4400 MB/s...any idea what gives? Using an HBA with 3008 chipset. The write is as expected; it's 2800 MB/s which is 700 MB/s advertised x 4.
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If I remove them from the stripe and test each individually, I get about the speeds you expect.
1060 MB/s read, 721 MB/s write approximately per device. Guess the Windows striping is not that great?
It's in a x16 3.0 slot.Have you tried striping just two drives? What slot is the HBA in? You might be running into slot bandwidth limitations.
I'm seeing approximately the same speeds on a 4 drive RAID-0. I'm using an Adaptec 8885e HBA (12gb/s 16 port native) which has a spec of 6.6GBps max. I can come close to that with a RAID-0 of 8x of these, so with only four of them 3.3GBps seems about right.It's in a x16 3.0 slot.
I get slightly better speeds in a Storage Spaces pool in S2016. 3681 MB/s read across 4 devices.
Would be great if someone could test their devices as well.
SAS still uses the 8b/10b encoding, thats 20% overhead (not including adressing and protocoll overhead)I guess I'm confused, even at 12 Gb/s, 1100 MB/s read per device is still under spec per lane for SAS3?
PCI-E 3.0 theoretical throughput is 8GT/s or ~985MBps per lane, full duplex. SAS 3008 based cards or the Adaptec 12gbps cards are all 8x lane cards.I guess I'm confused, even at 12 Gb/s, 1100 MB/s read per device is still under spec per lane for SAS3? 4.4 GB read for 4 devices is also still within spec. I checked out some spec sheets, SAS 3008 does 9.6 GB/s full duplex so I'm still at a loss discovering wherein the 3008 chipset is not able to handle 4 devices at line rate in a simple bench.
Of course that's why I said that benchmark is limited and to up the threads, you're getting what's expected, there is a little more to squeeze out but you're pretty much getting what's expected.I'm able to push slightly higher, up to around 4051 MB/s with higher queue depth and threads(128 QD, 24 threads), but at a certain point the setting doesn't add any performance. I guess it should be fine, at any rate, for my uses.