Re: Virtual I/O Caching Alpha/Oracle

On 26 Jan 96 09:55:55 GMT, Alan Greig <agreig_at_river.tay.ac.uk> wrote:
>In article <NEWTNews.822594935.7964.Bob_at_bobmc.gtionline.com>, Bob McGuire <Bob@Alpha> writes:
>> Greetings netters.
>>
>> Has anyone out in Netland attempted to change the
>> VCC_MAXSIZE parameters on an Alpha from the default of
>> 3200 to something greater? I'm trying to get the Alpha
>> running as best as possible with Oracle.
>
>On a general multi-user system we see a read hit rate of around
>90% with a 50MB cache:
>
> System Memory Resources on 26-JAN-1996 09:50:41.02
>
>Physical Memory Usage (pages): Total Free In Use Modified
> Main Memory (512.00Mb) 65536 23467 37827 4242
>
>Virtual I/O Cache
> Total Size (Kbytes) 50000 Read IO Count 5953058
> Free Kbytes 12648 Read Hit Count 5355658
> Kbytes in Use 37352 Read Hit Rate 89%
> Write IO Bypassing Cache 7268 Write IO Count 457392
> Files Retained 91 Read IO Bypassing Cache 252048
>
>>
>> If so, what have you changed the value to, and if there
>> were changes, how were they, good/bad/no change or simply
>> not worth the effort.
>
>On an system with 3.2 MB (default) I typically see a hit rate
>of under 50% if there's a lot of activity. So it is worth experimenting
>at least.

       Sorry about this followup but we are rather ignorant here (our
       doc wall is grey).  If I do a $ sh mem/cach/fu I get:

A400> sh mem/ca/fu
              System Memory Resources on 26-JAN-1996 12:48:58.13

Virtual I/O Cache
    Total Size (Kbytes)           3200    Read IO Count                      0
    Free Kbytes                   3200    Read Hit Count                     0
    Kbytes in Use                    0    Read Hit Rate                     0%
    Write IO Bypassing Cache         0    Write IO Count                     0
    Files Retained                   0    Read IO Bypassing Cache            0

A member of this cluster does not have Virtual I/O Cache capability. A400>

       To me this seems to mean our VIOC is not working at all.  Is this
       because we failed to enable if (if so, how do we enable it?) or
       because we are running a mixed cluster (the 5.5 systems are
       VAXen, the rest Alphas):

A400> sh clus
View of Cluster from system ID 1424  node: A400            26-JAN-1996 13:00:18
-------------------------------
|      SYSTEMS      | MEMBERS |
 -------------------------------

| A400   | VMS V6.2 | MEMBER  |
| SAT2   | VMS V5.5 | MEMBER  |
| SAT1   | VMS V5.5 | MEMBER  |
| ALF001 | VMS V6.2 | MEMBER  |
| M3300  | VMS V5.5 | MEMBER  |
| ALF002 | VMS V6.2 | MEMBER  |
-------------------------------


       Thanks for any hint,
       Michael