52.88. pg_shmem_allocations, missing units

Started by PG Bug reporting formover 3 years ago4 messagesdocs
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#1PG Bug reporting form
noreply@postgresql.org

The following documentation comment has been logged on the website:

Page: https://www.postgresql.org/docs/14/view-pg-shmem-allocations.html
Description:

Could someone add the units of size & allocated_size on the documentation
for pg_shmem_allocations? Currently there aren't any listed.

https://www.postgresql.org/docs/current/view-pg-shmem-allocations.html

Thanks,
rik.

#2Euler Taveira
euler@eulerto.com
In reply to: PG Bug reporting form (#1)
Re: 52.88. pg_shmem_allocations, missing units

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/

Attachments:

doc-shmem-alloc.difftext/x-patch; name=doc-shmem-alloc.diffDownload+2-2
#3Masahiko Sawada
sawada.mshk@gmail.com
In reply to: Euler Taveira (#2)
Re: 52.88. pg_shmem_allocations, missing units

On Mon, Aug 15, 2022 at 3:56 AM Euler Taveira <euler@eulerto.com> wrote:

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.

+1

The patch looks good to me.

Regards,

--
Masahiko Sawada
EDB: https://www.enterprisedb.com/

#4Daniel Gustafsson
daniel@yesql.se
In reply to: Masahiko Sawada (#3)
Re: 52.88. pg_shmem_allocations, missing units

On 15 Aug 2022, at 04:23, Masahiko Sawada <sawada.mshk@gmail.com> wrote:

On Mon, Aug 15, 2022 at 3:56 AM Euler Taveira <euler@eulerto.com> wrote:

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.

+1

The patch looks good to me.

Agreed, and adding the unit matches how other system views attributes like
pg_stat.avg_width. Will apply it in a bit.

--
Daniel Gustafsson https://vmware.com/