Re: [EXTERNAL] native i/o and RCAC - performance

[Jay Vaughn <jeffersonvaughn@xxxxxxxxx>]

row column access control

introduced to IBM os in 7.2

Jay

On Thu, May 13, 2021 at 8:59 AM Alan Shore via RPG400-L <
rpg400-l@xxxxxxxxxxxxxxxxxx> wrote:

> What is RCAC?
>
> Alan Shore
> Solutions Architect
> IT Supply Chain Execution
>
> [cid:image001.png@01D747D6.4D55A1B0]
>
> 60 Orville Drive
> Bohemia, NY 11716
> Phone [O] : (631) 200-5019
> Phone [C] : (631) 880-8640
> E-mail : ASHORE@xxxxxxxxxxxxxxxxxxxx
>
> 'If you're going through hell, keep going.'
> Winston Churchill
>
> From: RPG400-L [mailto:rpg400-l-bounces@xxxxxxxxxxxxxxxxxx] On Behalf Of
> Jay Vaughn
> Sent: Thursday, May 13, 2021 8:56 AM
> To: RPG programming on the IBM i (AS/400 and iSeries) <
> rpg400-l@xxxxxxxxxxxxxxxxxx>
> Subject: [EXTERNAL] native i/o and RCAC - performance
>
> Can anyone explain or even theorize when applying RCAC to a file, how it
> boosts the read performance of the file under native i/o?
>
> Example:
>
> file containing 5M rows...
> simple RPG pgm in for loop with reads...
>
> without RCAC applied
> elapsed time - 23s
> processing time - 1.544
>
> with RCAC applied (alter table theTable activate column access control)
> elapsed time - 4s
> processing time - 1.413
>
> drastic change in elapsed time - small change in processing time.
>
> There is also a smaller gain when using SQL but not as much as native i/o.
>
> tia
>
> Jay
> --
> This is the RPG programming on IBM i (RPG400-L) mailing list
> To post a message email: RPG400-L@xxxxxxxxxxxxxxxxxx<mailto:
> RPG400-L@xxxxxxxxxxxxxxxxxx>
> To subscribe, unsubscribe, or change list options,
> visit: https://lists.midrange.com/mailman/listinfo/rpg400-l<
> https://lists.midrange.com/mailman/listinfo/rpg400-l>
> or email: RPG400-L-request@xxxxxxxxxxxxxxxxxx<mailto:
> RPG400-L-request@xxxxxxxxxxxxxxxxxx>
> Before posting, please take a moment to review the archives
> at https://archive.midrange.com/rpg400-l<
> https://archive.midrange.com/rpg400-l>.
>
> Please contact support@xxxxxxxxxxxxxxxxxxxx<mailto:
> support@xxxxxxxxxxxxxxxxxxxx> for any subscription related questions.
>
> Help support midrange.com by shopping at amazon.com with our affiliate
> link: https://amazon.midrange.com<https://amazon.midrange.com>
> --
> This is the RPG programming on IBM i (RPG400-L) mailing list
> To post a message email: RPG400-L@xxxxxxxxxxxxxxxxxx
> To subscribe, unsubscribe, or change list options,
> visit: https://lists.midrange.com/mailman/listinfo/rpg400-l
> or email: RPG400-L-request@xxxxxxxxxxxxxxxxxx
> Before posting, please take a moment to review the archives
> at https://archive.midrange.com/rpg400-l.
>
> Please contact support@xxxxxxxxxxxxxxxxxxxx for any subscription related
> questions.
>
> Help support midrange.com by shopping at amazon.com with our affiliate
> link: https://amazon.midrange.com