[Info-vax] VSI OpenVMS V9.1 Field Test beginning.

[chris]

On 07/07/21 02:24, Stephen Hoffman wrote:
> On 2021-07-05 16:48:38 +0000, chris said:
>
>> On 07/02/21 18:29, John H. Reinhardt wrote:
>>
>>>
>>> 1.32 SupportedDiskTypes
>>> VSI OpenVMS x86-64 V9.1 only supports SATA disks. Support for other
>>> disk types will be added in future releases of VSI OpenVMS x86-64.
>>>
>>
>> Find that odd. SATA are consumer quality, 5400 or 7200 rpm. so slow
>> access compared to U320 scsi or sas at 10 or 15k...
>
> I can get ~half a gigabyte per second through a single SATA storage
> connection, sequential read or sequential write, on widely-available
> SATA (SATA 3.0 / SATA 6Gp/s) storage hardware.
>

That's with 7200 rpm drives, probably, whereas many are only 5400, so 
doubt that would be sustainable  bandwidth over large files, or where
the drive needs to seek or change track.

At 7200 rpm, track to track and rotational latency could be 8.4 
milliseconds worst case + head seek time, which limits sustainable 
bandwidth. 10K drives are better, 15K, even more so...