[Info-vax] VMS - The new file system. What do we know about it?...

[Stephen Hoffman]

On 2016-11-14 19:16:56 +0000, Michael Moroney said:

> Dirk Munk <munk at home.nl> writes:
> 
>> Modern disks of course use the Advanced Format structure, with 4kB  
>> blocks/sectors. Using arbitrary 512 byte blocks is possible, but not  
>> very good for performance. Is that taken into consideration?
> 
> That will have to be a separate project.  From what someone here told 
> me other OS's (Linux, Windoze) still use 4K block drives in 512 byte 
> block emulation mode.  Can anyone verify/refute this?

https://en.wikipedia.org/wiki/Advanced_Format
http://knowledge.seagate.com/ka030000000tlsfAAA
https://msdn.microsoft.com/en-us/library/windows/desktop/hh848035(v=vs.85).aspx
https://support.microsoft.com/en-us/kb/2510009
https://www.hgst.com/sites/default/files/resources/AFtechbrief.pdf
http://www.oracle.com/technetwork/articles/servers-storage-admin/solaris-advanced-format-disks-2344966.html 


Y'all +really+ need to get out more.

> Also, most VMS IO on itanics is through SAN storage servers, and they 
> are the ones that have to directly deal with 4K blocks.  I don't know 
> if storage servers themselves present themselves as using 4K blocks.

HPE was certainly seemingly more interested in selling FC SAN gear, and 
the software-based network attached storage I/O stacks tended to be 
lower performance than the hardware-based network-attached host 
controllers.   With flash storage so much faster, the competitive 
market for fast storage has opened up considerably, too — getting 
performance out of racks of hard disks was rather more complex, and 
there was a whole lot more iron involved in hard disks.

> Of course there are directly attached SCSI drives that could benefit,

Ayup; pretty much everything these days is SAS or SATA for the 
older-generation direct-attached storage.

> plus x86 is a different beast.

x86-64 has direct-attached, network-attached, and FC SAN gear available 
— same as everybody else.

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