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USB3 PCIe add-on cards?

Posted: 18 Mar 2015 02:12
by mobocracy
I have an old box I built as a VMware host 4-5 years ago and have been using as a lab box for 2012r2.

I've been tinkering with NAS4Free in a VM, doing stupid but frankly kind of cool stuff like building Raidz virtual devices using three different remote iSCSI volumes on three different devices, or using it to export local storage on an ESXi host as an iSCSI volume for access by the entire cluster.

I'm thinking about repurposing the 2012r2 box to tinker more seriously with NAS4Free. I'm curious what the current state of USB3 support is, especially for any reports of better-behaved USB3 PCIe add-in cards.

The current system has 4x 750GB SATA disk in it now and it's not quite enough to really justify the electricity it takes to turn it on for redundant storage of less than 2 TB formatted. The case it full and I'm not serious enough about it to justify swapping out all the disks, but if I could throw in a USB3 expansion card and tack on couple more 750 GB disks I have and maybe an old 256GB SSD as a cache the whole thing might be a lot more interesting.

But all that depends on USB3 support being reasonable and a supported/working add-in card.

I'm not really all that concerned about optimum performance as much as reasonable USB3 performance (which, IMHO, is pretty decent in my Windows experience) and basic stability (ie, works consistently). I know USB3 has been dodgy in FreeBSD (or at least that's what several threads have led me to believe) and often add-on port cards are of low quality, even if you try to buy a better unit.

IMHO USB3 deserves a little better attention, especially with 3.1 Gen 2 sporting 10 GB speeds. If you stop and think about it, the idea that you can spend under $2k and put 4x 1 GB SSDs on USB ports and get the kind of performance (throughput & IOPS) that only a couple of years ago took 8 GB FC and a $200k of SAN to deliver is pretty darn amazing.

Re: USB3 PCIe add-on cards?

Posted: 18 Mar 2015 07:21
by b0ssman
usb for storage is generally not recommended for nas4free especially for zfs.
usb3 support is still i a stage where its not recommended to be used.

if you want to attach drives externally please look into esata solutions.

Re: USB3 PCIe add-on cards?

Posted: 26 Mar 2015 19:51
by mobocracy
b0ssman wrote:usb for storage is generally not recommended for nas4free especially for zfs.
usb3 support is still i a stage where its not recommended to be used.

if you want to attach drives externally please look into esata solutions.
Heh, because you told me not to do it I just *had* to try.

I picked a cheap ($29) Rosewill USB3 add-in card (TI chipset). I plugged in a 128GB PNY USB stick. The system recognized it as USB3. I added it in as a disk, formatted it UFS and exported it as an iSCSI extent. Added it as a VMFS volume to VMware ESXi 5.5 and then added a new virtual disk to a Win7 vm and then formatted it NTFS within the VM. It all worked.

I then benchmarked it using CrystalDiskMark -- 77 MB/s read, 55MB/s write. Not *wow* performance, but certainly within acceptable limits for tertiary storage. This same box has 4xSATA disks in it in a RAIDZ1 configuration and the same iSCSI setup to the same VM benches at 98 MB/sec read and 57 MB/sec write so although USB3 is lesser performance, it's not that far off the spinning rust performance through several layers of abstraction.

Anyway, it's got a "it works" level of performance that makes it at least worth screwing around with more for the heck of it.