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From: "Dmitry A. Kazakov" <mailbox@dmitry-kazakov.de>
Subject: Re: Custom Storage Pool questions
Date: Tue, 21 Sep 2021 08:28:13 +0200	[thread overview]
Message-ID: <sibu1t$12ds$1@gioia.aioe.org> (raw)
In-Reply-To: sib9h5$njl$1@franka.jacob-sparre.dk

On 2021-09-21 02:37, Randy Brukardt wrote:
> "Dmitry A. Kazakov" <mailbox@dmitry-kazakov.de> wrote in message
> news:si77kd$rka$1@gioia.aioe.org...
> ...
>> 1. It is a massive overhead in both memory and performance terms with no
>> purpose whatsoever. I fail to see where that sort of thing might be even
>> marginally useful.
> 
> The classic example of Finalization is file management on a simple kernel (I
> use CP/M as the example in my head). CP/M did not try to recover any
> resources on program exit, it was the programs responsibility to recover
> them all (or reboot after every run). If you had holes in finalization, you
> would easily leak files and since you could only open a limited number of
> them at a time, you could easily make a system non-responsive.

This is why system resources are handled by the OS rather than by the 
application. But I do not see how this justifies "collections."

>> 2. What is worse that a collection is not bound to the pool. It is to an
>> access type, which may have a narrower scope. So the user could declare an
>> unfortunate access type, which would corrupt objects in the pool and the
>> pool designer has no means to prevent that.
> 
> Pools are extremely low-level things that cannot be safe in any sense of the
> word. A badly designed pool will corrupt everything. Using a pool with the
> "wrong" access type generally has to be programmed for (as I answered
> earlier, if I assume anything about allocations, I check for violations and
> do something else.) And a pool can be used with many access types; many
> useful ones are.

This is also true, but again unrelated to the point that tying 
finalization *without* deallocation to a pointer type is just wrong, 
semantically on any abstraction level.

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

  reply	other threads:[~2021-09-21  6:28 UTC|newest]

Thread overview: 97+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2021-09-13  0:53 Custom Storage Pool questions Jere
2021-09-13  5:29 ` Randy Brukardt
2021-09-14  1:04   ` Jere
2021-09-21  0:06     ` Randy Brukardt
2021-09-18 11:32   ` Simon Wright
2021-09-20  0:31   ` Jere
2021-09-20  6:34     ` Niklas Holsti
2021-09-20  6:48       ` Emmanuel Briot
2021-09-20  7:35         ` Dmitry A. Kazakov
2021-09-20 16:59         ` Shark8
2021-09-21  0:50         ` Randy Brukardt
2021-09-21 23:08           ` Jere
2021-09-28  4:42             ` Randy Brukardt
2021-10-02 23:19               ` Jere
2021-10-03  8:52                 ` Dmitry A. Kazakov
2021-10-14  1:26                   ` Randy Brukardt
2021-09-13 11:12 ` J-P. Rosen
2021-09-14  0:48   ` Jere
2021-09-14  6:08     ` J-P. Rosen
2021-09-15  0:39       ` Jere
2021-09-15  7:01         ` Simon Wright
2021-09-16 23:32           ` Jere
2021-09-20 23:51             ` Randy Brukardt
2021-09-21 22:40               ` Jere
2021-09-14  6:23     ` Dmitry A. Kazakov
2021-09-14  6:42       ` J-P. Rosen
2021-09-14  7:00         ` Dmitry A. Kazakov
2021-09-20 23:58         ` Randy Brukardt
2021-09-15  0:21       ` Jere
2021-09-15  6:54         ` Dmitry A. Kazakov
2021-09-20 23:48       ` Randy Brukardt
2021-09-14 10:54     ` Egil H H
2021-09-15  0:11       ` Jere
2021-09-15 16:43 ` Simon Wright
2021-09-15 17:03   ` Simon Wright
2021-09-15 19:07   ` Dmitry A. Kazakov
2021-09-15 20:40     ` Simon Wright
2021-09-16  7:12       ` Emmanuel Briot
2021-09-16 23:21         ` Jere
2021-09-17  7:08           ` Emmanuel Briot
2021-09-17  7:18           ` Simon Wright
2021-09-17 13:56           ` Dmitry A. Kazakov
2021-09-17 19:46             ` Simon Wright
2021-09-17 20:39               ` Dmitry A. Kazakov
2021-09-17 21:17                 ` Niklas Holsti
2021-09-18  7:49                   ` Dmitry A. Kazakov
2021-09-18  9:03                     ` Niklas Holsti
2021-09-18 10:22                       ` Dmitry A. Kazakov
2021-09-18 15:59                         ` Niklas Holsti
2021-09-18 16:19                           ` Dmitry A. Kazakov
2021-09-19 10:36                             ` Niklas Holsti
2021-09-19 11:41                               ` Dmitry A. Kazakov
2021-09-20  7:05                                 ` Niklas Holsti
2021-09-20  7:35                                   ` Dmitry A. Kazakov
2021-09-20  8:08                                     ` Niklas Holsti
2021-09-20  8:28                                       ` Dmitry A. Kazakov
2021-09-21  0:45                                         ` Randy Brukardt
2021-09-21  0:40                                       ` Randy Brukardt
2021-09-21  0:30                                 ` Randy Brukardt
2021-09-21  0:37                                 ` Randy Brukardt
2021-09-21  6:28                                   ` Dmitry A. Kazakov [this message]
2021-09-28  4:38                                     ` Randy Brukardt
2021-09-28  7:00                                       ` Dmitry A. Kazakov
2021-09-21  0:26                         ` Randy Brukardt
2021-09-21  6:51                           ` Dmitry A. Kazakov
2021-09-28  4:31                             ` Randy Brukardt
2021-09-28  6:56                               ` Dmitry A. Kazakov
2021-09-28  7:52                                 ` Simon Wright
2021-09-28  8:07                                   ` Dmitry A. Kazakov
2021-09-28 22:04                                     ` Randy Brukardt
2021-09-29  7:57                                       ` Dmitry A. Kazakov
2021-09-29 14:41                                         ` Shark8
2021-09-29 15:16                                           ` Dmitry A. Kazakov
2021-09-30  0:16                                             ` Randy Brukardt
2021-09-30  8:08                                               ` Dmitry A. Kazakov
2021-10-01  0:04                                                 ` Randy Brukardt
2021-10-01  8:25                                                   ` Dmitry A. Kazakov
2021-10-02  9:06                                                     ` Randy Brukardt
2021-10-02 10:18                                                       ` Dmitry A. Kazakov
2021-10-03  4:33                                                         ` Randy Brukardt
2021-10-03  8:40                                                           ` Dmitry A. Kazakov
2021-10-14  1:21                                                             ` Randy Brukardt
2021-10-14  3:12                                                               ` philip...@gmail.com
2021-10-14  7:31                                                               ` Dmitry A. Kazakov
2021-10-15  0:36                                                                 ` Randy Brukardt
2021-10-15  8:08                                                                   ` Stephen Leake
2021-10-15  8:18                                                                     ` Dmitry A. Kazakov
2021-10-15 22:22                                                                     ` Randy Brukardt
2021-10-15  8:15                                                                   ` Dmitry A. Kazakov
2021-10-15 22:44                                                                     ` Randy Brukardt
2021-10-16  9:00                                                                       ` Dmitry A. Kazakov
2021-10-16 14:32                                                                         ` Simon Wright
2021-10-16 15:06                                                                           ` Dmitry A. Kazakov
2021-10-18 14:23                                                                             ` Shark8
2021-09-21  0:19                     ` Randy Brukardt
2021-09-21  0:18                 ` Randy Brukardt
2021-09-16  8:41       ` Dmitry A. Kazakov
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