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Date: Sun, 14 Aug 2022 15:55:32 -0300
From: "Euler Taveira" <euler@eulerto.com>
To: coleman.rik@gmail.com, pgsql-docs@lists.postgresql.org
Subject: Re: 52.88. pg_shmem_allocations, missing units
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On Fri, Aug 12, 2022, at 5:43 PM, PG Doc comments form wrote:
> Could someone add the units of size & allocated_size on the documentation
> for pg_shmem_allocations?  Currently there aren't any listed.
According to ShmemIndexEnt struct:

/* this is a hash bucket in the shmem index table */
typedef struct
{
    char        key[SHMEM_INDEX_KEYSIZE];   /* string name */
    void       *location;       /* location in shared mem */
    Size        size;           /* # bytes requested for the structure */
    Size        allocated_size; /* # bytes actually allocated */
} ShmemIndexEnt;

The unit is bytes. A patch is attached to add such information.


--
Euler Taveira
EDB   https://www.enterprisedb.com/

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<!DOCTYPE html><html><head><title></title><style type=3D"text/css">p.Mso=
Normal,p.MsoNoSpacing{margin:0}</style></head><body><div>On Fri, Aug 12,=
 2022, at 5:43 PM, PG Doc comments form wrote:<br></div><blockquote type=
=3D"cite" id=3D"qt" style=3D""><div>Could someone add the units of size =
&amp; allocated_size on the documentation<br></div><div>for pg_shmem_all=
ocations?&nbsp; Currently there aren't any listed.<br></div></blockquote=
><div>According to ShmemIndexEnt struct:<br></div><div><br></div><div>/*=
 this is a hash bucket in the shmem index table */<br></div><div>typedef=
 struct<br></div><div>{<br></div><div>&nbsp;&nbsp;&nbsp; char&nbsp;&nbsp=
;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; key[SHMEM_INDEX_KEYSIZE];&nbsp;&nbsp; /*=
 string name */<br></div><div>&nbsp;&nbsp;&nbsp; void&nbsp;&nbsp;&nbsp;&=
nbsp;&nbsp;&nbsp; *location;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; /* loca=
tion in shared mem */<br></div><div>&nbsp;&nbsp;&nbsp; Size&nbsp;&nbsp;&=
nbsp;&nbsp;&nbsp;&nbsp;&nbsp; size;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&=
nbsp;&nbsp;&nbsp;&nbsp; /* # bytes requested for the structure */<br></d=
iv><div>&nbsp;&nbsp;&nbsp; Size&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp=
; allocated_size; /* # bytes actually allocated */<br></div><div>} Shmem=
IndexEnt;<br></div><div><br></div><div>The unit is bytes. A patch is att=
ached to add such information.<br></div><div><br></div><div><br></div><d=
iv id=3D"sig112409080"><div class=3D"signature">--<br></div><div class=3D=
"signature">Euler Taveira<br></div><div class=3D"signature">EDB&nbsp;&nb=
sp; <a href=3D"https://www.enterprisedb.com/">https://www.enterprisedb.c=
om/</a><br></div></div><div><br></div></body></html>
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