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From: "Dmitry A. Kazakov" <mailbox@dmitry-kazakov.de>
Subject: Re: Performance of records with variant parts
Date: Mon, 22 Mar 2021 18:39:54 +0100	[thread overview]
Message-ID: <s3akp6$jdu$1@gioia.aioe.org> (raw)
In-Reply-To: 07a56dcc-9e17-49b2-a980-3a5a2d265cedn@googlegroups.com

On 2021-03-22 18:02, John Perry wrote:

> Is there a reason that the record with variant parts runs so much slower? I can make the complete source available if need be.

It must check the discriminant if the object is dynamically constrained. 
Checking the discriminant and accessing a scalar field is roughly in the 
same league, so 15-30% penalty is a quite good outcome. I would expect 
50% or even worse with cache misses between independent memory accesses.

-- 
Regards,
Dmitry A. Kazakov
http://www.dmitry-kazakov.de

  parent reply	other threads:[~2021-03-22 17:39 UTC|newest]

Thread overview: 24+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2021-03-22 17:02 Performance of records with variant parts John Perry
2021-03-22 17:32 ` Jeffrey R. Carter
2021-03-22 17:49   ` John Perry
2021-03-22 17:54     ` John Perry
2021-03-22 19:31     ` Jeffrey R. Carter
2021-03-22 22:11       ` John Perry
2021-03-23  9:31         ` Jeffrey R. Carter
2021-03-23 14:27           ` Simon Wright
2021-03-23 23:00           ` John Perry
2021-03-23 23:27             ` Jeffrey R. Carter
2021-03-26 15:38               ` Stephen Leake
2021-03-26 15:44                 ` John Perry
2021-03-30  7:12                   ` Emmanuel Briot
2021-04-01  0:03                     ` John Perry
2021-04-01  6:45                       ` Emmanuel Briot
2021-04-01 13:38                       ` Niklas Holsti
2021-04-02 16:07                         ` John Perry
2021-03-22 17:39 ` Dmitry A. Kazakov [this message]
2021-03-22 17:45   ` John Perry
2021-03-22 18:07     ` Dmitry A. Kazakov
2021-03-22 18:23       ` John Perry
2021-03-22 20:30         ` Dmitry A. Kazakov
2021-03-22 18:59 ` Niklas Holsti
2021-03-22 21:54   ` John Perry
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