From: Tom Lane <tgl@sss.pgh.pa.us>
To: Tomas Vondra <tv@fuzzy.cz>
cc: Andres Freund <andres@anarazel.de>, Simon Riggs <simon@2ndquadrant.com>,
        pgsql-committers <pgsql-committers@postgresql.org>,
        Andrew Dunstan <andrew@dunslane.net>
Subject: Re: pgsql: Generational memory allocator
In-reply-to: <31255.1511497154@sss.pgh.pa.us>
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Comments: In-reply-to Tom Lane <tgl@sss.pgh.pa.us>
	message dated "Thu, 23 Nov 2017 23:19:14 -0500"
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Date: Fri, 24 Nov 2017 14:13:12 -0500
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I wrote:
> Tomas Vondra <tv@fuzzy.cz> writes:
>> Thanks. Do we need to do something similar to the other memory contexts? 
>> I see Slab does not do this at all (assuming it's not necessary), and 
>> AllocSet does this in a different way (which seems a bit strange).

> Hm ... the coding in AllocSet is ancient and I have to say that I don't
> like it as well as what I put into generation.c.

I take that back: the current coding of padding in AllocChunkData only
dates back to 7e3aa03b.  But I still don't like it, and will migrate
generation.c's version into aset.c.  And maybe improve the comments.

BTW, it appears that some of the confusion in generation.c can be
accounted for by not having entirely followed the changes in 7e3aa03b.

			regards, tom lane