Re: qtemp performance oddity.

On 28 Feb 2013 08:02, Dan Kimmel wrote:

RCLSTG is probably the answer; whatever you can do to rebuild the
look-aside map. All the QTEMP stuff goes in a separate range of
single-level-storage addresses, because when the job ends all the
memory and disk sectors go right back into the available pool.
Adding the extra memory may have spread the look-aside map into a
place where it isn't efficient.

Except what the RCLSTG will do if\for including a refresh of the *DBXREF, I do not expect that the RCLSTG request would assist.

I am not sure to what a "look-aside map" refers, but I doubt the RCLSTG will change whatever it is.

The QTEMP library, while its name might imply "temporary", is not temporary storage. The external objects in QTEMP are also not created with temporary storage addresses. Those objects are permanent objects in the address range of permanent objects. Besides, the reclaim storage only processes the permanent storage directory, so if the QTEMP and its objects were in the temporary storage directory, they would never be visible to the Reclaim Storage request. AFaIK the reclaim storage does nothing about permanent\temporary address range location, nor /where/ objects and data reside. The primary functions of RCLSTG are ownership recovery [every permanent object must have an owner; e.g. QDFTOWN], context recovery [assignment to permanent objects incorrectly found out of a context; aka library, or similarly a directory], destroying objects with invalid object types and orphan objects that are not data and for which no parent was created for its re-association, and damage notification, plus there are various other /component-specific/ actions that typically refresh their views of what is actually available on the system. The RECLAIM MI instruction basically starts multiple LIC tasks to generate object lists from subsets of the permanent storage directly.... and each object list is passed to the OS to perform the aforementioned work [i.e. the "primary function" of the reclaim].