AW: Re: Is first page always backed by real storage upon return from STORAGE OBTAIN?

>>Allocating 100 MB area, I found that the first page in the newly allocated >>area always seems to be backed by real storage upon return from STORAGE >>OBTAIN. >Before or after actual reference? I tought "upon return from STORAGE OBTAIN" would be clear. Anyway, no I have not referenced any

Re: Is first page always backed by real storage upon return from STORAGE OBTAIN?

On Wed, 2 Dec 2015 14:12:04 +, Blaicher, Christopher Y. wrote: >If you are doing anything other than a full page, or full pages, STORAGE >OBTAIN, >the system has to put a FQE element in the top of the page I've never seen an FQE located within the area containing the free space. The data

AW: Re: Is first page always backed by real storage upon return from STORAGE OBTAIN?

> Do you specify BNDRY=PAGE? No, but from what the manual says I guess in my case the rule "8192 or more from pageable, private subpool" applies", so the storage is cleared. I was just expecting that the backing and clearing only takes place when I access the storage. > Are you using

AW: Re: Is first page always backed by real storage upon return from STORAGE OBTAIN?

>If you are doing anything other than a full page, or full pages, STORAGE >OBTAIN, the system has to put a FQE element in the top of the page, and so it >would have to back the first virtual page with a real page. I'm allocating 10MiB, that is to work like fill page, I assume. IPCS tells me

at Re: AW: Re: Is first page always backed by real storage upon return from STORAGE OBTAIN?

Peter: It's been several years since I had a hand in that code (as the team leader of the VSM development team for the first release of MVS back in 1972-1974), but someone mentioned the existence of the FQE (Free Queue Element). The FQE described the number of bytes that were free within the

Re: AW: Re: Is first page always backed by real storage upon return from STORAGE OBTAIN?

Peter, > I'm allocating 10MiB, that is to work like fill page, I assume. IPCS tells me > the full page is X'00', so there is nothing written in that page. > As said in another response, it's pure curiosity. ask IPCS if the first page is really backed (ip rsmdata virtpage ra(x'page address'))

Re: AW: Re: Is first page always backed by real storage upon return from STORAGE OBTAIN?

On 2 December 2015 at 13:38, nitz-ibm wrote: > ask IPCS if the first page is really backed (ip rsmdata virtpage ra(x'page > address')) and check the flags in the output. He already knows that *his* first page is backed; he's asking if this is always the case. Tony H.

Re: Is first page always backed by real storage upon return from STORAGE OBTAIN?

> Allocating 100 MB area, I found that the first page in the newly > allocated area always seems to be backed by real storage upon return > from STORAGE OBTAIN. Is this true? Where is this documented? For requests where RSM is involved: If you specify BACK=ALL or BACK=NONE on the STORAGE macro,

AW: Re: AW: Re: Is first page always backed by real storage upon return from STORAGE OBTAIN?

>> ask IPCS if the first page is really backed (ip rsmdata virtpage ra(x'page >> address')) and check the flags in the output. > He already knows that *his* first page is backed; he's asking if this is > always the case. Well, at least I think I know it is backed from what IPCS tells me.

Re: at Re: AW: Re: Is first page always backed by real storage upon return from STORAGE OBTAIN?

> It's been several years since I had a hand in that code (as the team > leader of the VSM development team for the first release of MVS back in > 1972-1974), but someone mentioned the existence of the FQE (Free Queue > Element). The FQE described the number of bytes that were free within >

Is first page always backed by real storage upon return from STORAGE OBTAIN?

Allocating 100 MB area, I found that the first page in the newly allocated area always seems to be backed by real storage upon return from STORAGE OBTAIN. Is this true? Where is this documented? -- Peter Hunkeler -- For

Re: Is first page always backed by real storage upon return from STORAGE OBTAIN?

Peter Hunkeler wrote: >Allocating 100 MB area, I found that the first page in the newly allocated >area always seems to be backed by real storage upon return from STORAGE >OBTAIN. Before or after actual reference? Say you execute some instructions after STORAGE OBTAIN, do you observe that

Re: Is first page always backed by real storage upon return from STORAGE OBTAIN?

On Wed, 2 Dec 2015 14:06:28 +0100, Peter Hunkeler wrote: >Allocating 100 MB area, I found that the first page in the newly >allocated area always seems to be backed by real storage upon >return from STORAGE OBTAIN. Do you specify BNDRY=PAGE? Are you using z/OS 1.9 rules or z/OS 1.10 rules? How

Re: Is first page always backed by real storage upon return from STORAGE OBTAIN?

Marchant Sent: Wednesday, December 02, 2015 9:03 AM To: IBM-MAIN@LISTSERV.UA.EDU Subject: Re: Is first page always backed by real storage upon return from STORAGE OBTAIN? On Wed, 2 Dec 2015 14:06:28 +0100, Peter Hunkeler wrote: >Allocating 100 MB area, I found that the first page in the ne

Re: Is first page always backed by real storage upon return from STORAGE OBTAIN?

In <7481950488678847.wa.m42tomibmmainyahoo@listserv.ua.edu>, on 12/02/2015 at 10:02 AM, Tom Marchant <000a2a8c2020-dmarc-requ...@listserv.ua.edu> said: >I've never seen an FQE located within the area containing the free >space. Newby. From IBM System/3S0 Operating System: Programmer's