[Info-vax] Command to show process rms file opens?

[Stephen Hoffman]

On 2020-07-31 16:45:25 +0000, Chris Scheers said:

> David Hittner wrote:
>> The system in question is:
>> Integrity rx2660, 2x 2C CPUs, hyperthreading enabled (8 virtual CPUs)
>> P800 SAS Controller w/ 512 cache, write cache currently disabled due to 
>> low battery voltage
>> 7x 146GB 10K SAS drives in a RAID-5 array

That's a very big performance hit right there, non-cached RAID-5 HDD.

>> 2x logical drives built on the RAID-5 array, System drive is 25%, Data 
>> drive is 75%
>> HPE OpenVMS 8.4 U7
>> HPE MMS 12.8
>> ...
> 
> I understand the pain of the P800 battery.
> 
> However, the lack of the write cache on the P800 will hurt you big time.
> 
> Also, the HP 300GB (and even 600GB) drives are very inexpensive these 
> days.  They are also considerably faster (even without cache) than the 
> 146GB drives.
> 
> You could replace your drives with 8x300GB drives configured as 
> shadowed stripe sets (not RAID-5) and you would have much better 
> performance and still have redundancy.

Yep.

Going price for an HPE SFF 240 GB SATA SSD is USD$350. Might be able to 
find those cheaper, that was a _very_ quick look.

But I'd fix the dead cache battery and the use of RAID-5 first.  Fix 
those issues, and add a shelf of SSDs maybe demoting the HDDs to 
archival and backup use, and this box will be vastly faster.

For approximately no software effort.

Yeah, this could be CPU or memory constraints too, and T4 or SPM or 
otherwise can help with that determination, but non-cached HDDs on 
RAID-5 are almost certainly going to be I/O saturated.

MONITOR DISK/ITEM=QUEUE past 0.5 is bad news, and I'll wager that 
you're far past 0.5 during a build.



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