List Info

Thread: Re: Getting all instances without associations
Re: Getting all instances without associations
user name
 2008-06-04 14:48:00 

  


  

    
OFTEN IT IS BEST TO JUST GET ALL THE INSTANCE OF ALL THE CLASSES INVOLVED, AND THEN DO YOUR OWN QUERY LOCALLY.
THAT IS BECAUSE FOR A QUERY, ONE WOULD HAVE TO GET EACH INSTANCE OF THE FIRST ELEMENT IN THE QUERY, AND THEN GET EVERY INSTANCE OF THE NEXT ELEMENT IN THE QUERY FOR  EVERY PRECEDING ELEMENT, ETC. OVER AND OVER, WHICH EXPANDS GEOMETRICALLY.
IF YOU CONTROL THE PROVIDER, THEN YOU CAN IMPLEMENT THE QUERY RESPONSE IN THAT, BUT OTHERWISE THERE IS NOTHING THE REPOSITORY CAN DO.  IT WOULD HAVE TO GET ALL THE INSTANCES AS WELL, AND TAKE JUST AS LONG AS IT WOULD FOR YOU.

----- ORIGINAL MESSAGE ----
FROM: YVES
 <EXPI_TRASHWEB.DE>
TO: PEGASUS-LOPENPEGASUS.ORG
SENT: WEDNESDAY, JUNE 4, 2008 12:06:34 PM
SUBJECT: RE: GETTING ALL INSTANCES WITHOUT ASSOCIATIONS


THANKS FOR YOUR RESPONSE!

DO YOU MEAN SOMETHING LIKE THAT (IN PSEUDOCODE):
--------------
GETALLVOLUMEINSTANCES();
GETALLVOLUMETOVOLUMEGROUPASSOCIATIONS();
FOREACH(VOLUMEINSTANCE)
{
&NBSP; &NBSP; FOREACH(VOLUMETOVOLUMEGROUPASSOCIATION)
&NBSP; &NBSP; {
&NBSP; &NBSP; &NBSP; &NBSP; IF(?¿VOLUMETOVOLUMEGROUPASSOCIATION.VOLUMEPATH
== ?¿VOLUMEINSTANCE.GETPATH())
&NBSP; &NBSP; &NBSP; &NBSP; {
&NBSP; &NBSP; &NBSP; &NBSP; &NBSP; &NBSP; DOSTUFFWITHUNASSOCIATEDVOLUME();
&NBSP; &NBSP; &NBSP; &NBSP; &NBSP; &NBSP; BREAK;
&NBSP; &NBSP; &NBSP; &NBSP; }
&NBSP; &NBSP; }
}
-------------

OR IS THERE A BUILT-IN FUNCTIONALITY OF OPENPEGASUS FOR THIS?

>; UNLIKE DATABASE MANAGERS, QUERY SUPPORT ARE NOT BUILT INTO CIMOMS.&NBSP; EXECQUERY NEEDS TO BE EXPLICITLY SUPPORTED BY THE PROVIDER. I SUSPECT THE QUERY FUNCTIONALITY YOU ARE LOOKING FOR IS NOT AVAILABLE IN ANY QL.
> 
> YOU SHOULD BE ABLE TO
 ENUMERATEINSTANCS OF IBMTSDS_VOLUME&NBSP; AND WHATEVER ASSOCIATIONS CONNECTS IBMTSDS_VOLUME&NBSP; AND IBMTSDS_VOLUMEGROUP - THEN DO ALL THE FILTERING LOCALLY.&NBSP; THIS SAVES THE ONE-BY-ONE MANY TRANSACTIONS, BUT YOU MAY GET SCALABILITY ISSUES (AS WITH QUERY) IF THE RESPONSE IS HUGE.
> 
> PAUL



  

  
  
   
     
    

  

    RE: Getting all instances without
associations
  


  

     user name

     2008-06-04 15:31:03
  


  

    

  


  

    





Paul alluded to this with his scalability comment... but keep in
mind that a storage array could return large numbers of Volume instances in the
response to "getAllVolumeInstances()&quot;  (Some arrays I know of would
return 65,536 when fully populated).



 



~edh



 









From: Kirk Augustin
[mailto:kirk_augustinyahoo.com] 

Sent: Wednesday, June 04, 2008 12:48 PM

To: yves; pegasus-lopenpegasus.org

Subject: Re: Getting all instances without associations









 










Often it is best to just get all the
instance of all the classes involved, and then do your own query locally.


That is because for a query, one would have to get each instance of the first
element in the query, and then get every instance of the next element in the
query for  every preceding element, etc. over and over, which expands
geometrically.

If you control the provider, then you can implement the query response in that,
but otherwise there is nothing the repository can do.  It would have to
get all the instances as well, and take just as long as it would for you.






----- Original Message ----

From: yves <expi_trashweb.de>

To: pegasus-lopenpegasus.org

Sent: Wednesday, June 4, 2008 12:06:34 PM

Subject: RE: Getting all instances without associations



Thanks for your response!



Do you mean something like that (in pseudocode):

--------------

GetAllVolumeInstances();

GetAllVolumeToVolumegroupAssociations();

foreach(VolumeInstance)

{


    foreach(VolumeToVolumegroupAssociation)

&nbsp;   {

        if(VolumeToVolumegroupAssociation.VolumePath

== VolumeInstance.getPath())

&nbsp;       {

            DoStuffWithUnassociatedVolume();

            break;

&nbsp;       }

    }

}

-------------



Or is there a built-in functionality of OpenPegasus for this?




> Unlike database managers, query support are not built into CIMOMs.&nbsp;
ExecQuery needs to be explicitly supported by the provider. I suspect the query
functionality you are looking for is not available in any QL.

> 

> You should be able to EnumerateInstancs of IBMTSDS_Volume  and
whatever associations connects IBMTSDS_Volume  and IBMTSDS_Volumegroup -
then do all the filtering locally.&nbsp; This saves the one-by-one many
transactions, but you may get scalability issues (as with query) if the
response is huge.

&gt; 

> Paul




















  

  
  
   
     
    

  

    RE: Getting all instances without
associations
  


  

     user name

     2008-06-05 09:41:30
  


  

    

  


  

    

... and wasn't there an email message recently&nbsp;from 
one of the clients that the client code was running out of memory because it 
could not swallow that much information coming from the Provider?&nbsp; Granted, 
one can say, just beef up the client software; however, the general trend is to 
put the resources on the server side so that the client software can be as 
"thin" as possible.


 



/Mike







From: Houston, Eddie 
[mailto:eddie.houstonhp.com] 
Sent: Wednesday, June 04, 2008 4:31 
PM
To: Kirk Augustin; yves; 
pegasus-lopenpegasus.org
Subject: RE: Getting all instances without 
associations







Paul 
alluded to this with his scalability comment... but keep in mind that a storage 
array could return large numbers of Volume instances in the response to 
"getAllVolumeInstances()" ; (Some arrays I know of would return 65,536 when 
fully populated).


 


~edh


 






From: Kirk Augustin 
[mailto:kirk_augustinyahoo.com] 
Sent: Wednesday, June 04, 2008 12:48 
PM
To: yves; pegasus-lopenpegasus.org
Subject: Re: Getting 
all instances without associations


 







Often it is best to 
just get all the instance of all the classes involved, and then do your own 
query locally.
That is because for a query, one would have to get each 
instance of the first element in the query, and then get every instance of the 
next element in the query for  every preceding element, etc. over and over, 
which expands geometrically.
If you control the provider, then you can 
implement the query response in that, but otherwise there is nothing the 
repository can do.  It would have to get all the instances as well, and 
take just as long as it would for you.




----- Original Message 
----
From: yves <expi_trashweb.de>
To: 
pegasus-lopenpegasus.org
Sent: Wednesday, June 4, 2008 12:06:34 
PM
Subject: RE: Getting all instances without associations

Thanks for 
your response!

Do you mean something like that (in 
pseudocode):
--------------
GetAllVolumeInstances();
GetAllVolumeToVolumegroupAssociations();
foreach(VolumeInstance)
{
  
  foreach(VolumeToVolumegroupAssociation)
&nbsp;   {
  
      if(VolumeToVolumegroupAssociation.VolumePath
== 
VolumeInstance.getPath())
&nbsp;       {
    
        DoStuffWithUnassociatedVolume();
    
        break;
&nbsp;       }
  
  }
}
-------------

Or is there a built-in functionality of 
OpenPegasus for this?

>; Unlike database managers, query support are 
not built into CIMOMs.&nbsp; ExecQuery needs to be explicitly supported by the 
provider. I suspect the query functionality you are looking for is not available 
in any QL.
> 
> You should be able to EnumerateInstancs of 
IBMTSDS_Volume ; and whatever associations connects IBMTSDS_Volume  and 
IBMTSDS_Volumegroup - then do all the filtering locally.&nbsp; This saves the 
one-by-one many transactions, but you may get scalability issues (as with query) 
if the response is huge.
> 
> 
Paul


  

  
  
   
     
    






 [1-3]











   
 





about | contact  Other archives ( Real Estate discussion Medical topics )