[Info-vax] 3rd party SATA SSD usage on RX2660+P400 in a production environment?

[Stephen Hoffman]

On 2019-07-03 19:27:56 +0000, David Turner said:

> Strange as VMS is installed on a RAID1 HGST SSD set I use for testing

Searches for HGST SAS Drives 12G turned up a whole bunch of 
bigger-than-OpenVMS-can-address HGST HDDs, and no SSDs.

Hanging a SAS-3 SSD drive (12G) off a SAS-1 (3G) controller works, but 
certainly not getting all of what the SSDs can do.

Hanging a SAS-3 HDD off a SAS-1 controller is kinda silly.  Not unless 
the "HDD" has a whole lot of flash, or some other optimization.  HDDs 
just aren't that fast.

HGST hard disks are among the more reliable options.  Haven't worked 
(knowingly) with any HGST SSDs, though.

> 
> On 7/1/2019 12:04 PM, Stephen Hoffman wrote:
>> On 2019-07-01 01:29:14 +0000, David Turner said:
>> 
>>> Well, Rod, I have unused HGST SAS Drives 12G that are nowhere near your 
>>> pricing and I have them in stock and I have tested them with VMS on HPE 
>>> Integrity rx2800 i4 and i2. No doubt they work but use a P800 and a 
>>> PCI-e/PCI-X backplane. The crappy onboard controller on the rx2660 
>>> cannot handle anything (512Mbit/sec) compared with the P800 at 3Gbit or 
>>> even the P812 6Gbit (works great with SSD)
>> 
>> HDDs are ~100 to 200 IOPS or so per spindle whether helium or 
>> otherwise, versus as much as 100,000 IOPS with SSD.
>> 
>> And OpenVMS can't address any storage volume past 2 TiB prior to VSI 
>> VAFS, so those HGST SAS drives won't work with OpenVMS.
>> 
>> Not prior to OpenVMS V9.2 or so, or whenever VAFS becomes available. Or 
>> not without controller-level partitioning or controller-provided 
>> storage virtualization.


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