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From: Jacob Champion <jacob.champion@enterprisedb.com>
Date: Mon, 25 Mar 2024 16:21:40 -0700
Message-ID: <CAOYmi+=rFhT_muEeaUP6eJ-NETkfaPRbehrrdYD5+1S5fbfXqw@mail.gmail.com>
Subject: Re: WIP Incremental JSON Parser
To: Andrew Dunstan <andrew@dunslane.net>
Cc: Robert Haas <robertmhaas@gmail.com>, Peter Smith <smithpb2250@gmail.com>, 
	PostgreSQL Hackers <pgsql-hackers@lists.postgresql.org>
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On Mon, Mar 25, 2024 at 4:12=E2=80=AFPM Jacob Champion
<jacob.champion@enterprisedb.com> wrote:
> Stack size should be pretty limited, at least on the platforms I'm
> familiar with. So yeah, the recursive descent will segfault pretty
> quickly, but it won't repalloc() an unbounded amount of heap space.
> The alternative would just be to go back to a hardcoded limit in the
> short term, I think.

And I should mention that there are other ways to consume a bunch of
memory, but I think they're bounded by the size of the JSON file.
Looks like the repalloc()s amplify the JSON size by a factor of ~20
(JS_MAX_PROD_LEN + sizeof(char*) + sizeof(bool)). That may or may not
be enough to be concerned about in the end, since I think it's still
linear, but I wanted to make sure it was known.

--Jacob