[Info-vax] RX2800 sporadic disk I/O slowdowns

[Volker Halle]

Am 18.10.2024 um 20:26 schrieb Richard Jordan:

> We periodically (sometimes steady once a week, but sometimes more 
> frequent) one overnight batch job take much longer than normal to run. 
> Normal runtime about 30-35 minutes will take 4.5 - 6.5 hours.  Several 
> images called by that job all run much slower than normal.  At the end 
> the overall CPU and I/O counts are very close between a normal and a 
> long job.

If 'overall CPU and I/O counts' are about the same, please re-consider 
my advice to run T4. Look at the disk response times and I/O queue 
length and compare a 'good' and a 'slow' run.

If 'the problem' would be somewhere in the disk IO sub-system, changing 
RMS buffers will only 'muddy the waters'.

Volker.