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From: Simon Wright <simon@pushface.org>
Newsgroups: comp.lang.ada
Subject: Re: Why couldn't an operating system be written in ada
Date: Thu, 28 Feb 2019 08:28:03 +0000
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Date: 2019-02-28T08:28:03+00:00
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G. B. <nonlegitur@nmhp.invalid> writes:

> Patrick Jakubowski <patrick.jakubowski@googlemail.com> wrote:
>>  I am curious myself if I could prepare and provoke ADA to keep data
>> structures in L1 cache.
>> 
>
> You can. (I wouldn‘t know, though, how to have the ADA (organization)
> store things in a cache.) The idea is that Ada (the language) lets the
> programmer express, with relative ease, what needs to be known to
> safely disable checks. And then, also, the run-time system can be
> minimized, even zeroed.

I found a paper on cache-conscious data structures[1], which was much
more interested in locality than in detailed representation. If you have
a large data structure, better to have the 'hot' parts of an individual
node in a smaller object, so they stand more chance of getting into the
same cache line, with the 'cold' parts kept elsewhere.

Looked like a lot of work, it'd have to be worth it.

[1] https://www.microsoft.com/en-us/research/wp-content/uploads/2016/12/ccds.pdf