Re: pg_trgm upgrade to 1.6 led to load average increase

On Tuesday, January 20th, 2026 at 17:34, Adrian Klaver <adrian(dot)klaver(at)aklaver(dot)com> wrote:

>
>
> On 1/20/26 00:50, Nicolas Seinlet wrote:
>
> > Hello,
> >
> > we've upgraded the pg_trgm extension from 1.0 to 1.6 on our production
> > database, while sticking our postgresql cluster version to 16. This led
> > to an increase in the load average of the server (twice the load average
> > on our use case). After investigation, we found our issue was linked to :
> > https://github.com/postgres/postgres/
> > commit/935f6666502250abde8615bc7805a6e5aa05a066 <https://github.com/
> > postgres/postgres/commit/935f6666502250abde8615bc7805a6e5aa05a066>
> >
> > We issue queries like :
> > SELECT model, res_id FROM ir_model_data WHERE module='base' AND
> > name='public_user';
>
>
>
> You need to provide the table definition, including indexes.
>

Hello,

here is the table definition:

Table "public.ir_model_data"
Column | Type | Collation | Nullable | Default
-------------+-----------------------------+-----------+----------+-------------------------------------------
id | integer | | not null | nextval('ir_model_data_id_seq'::regclass)
create_uid | integer | | |
create_date | timestamp without time zone | | | timezone('UTC'::text, now())
write_date | timestamp without time zone | | | timezone('UTC'::text, now())
write_uid | integer | | |
noupdate | boolean | | | false
name | character varying | | not null |
module | character varying | | not null |
model | character varying | | not null |
res_id | integer | | |
Indexes:
"ir_model_data_pkey" PRIMARY KEY, btree (id)
"ir_model_data_create_uid_idx" btree (create_uid) WHERE create_uid IS NOT NULL AND (create_uid <> ALL (ARRAY[1, 208196]))
"ir_model_data_model_name_multilang_index" btree (name) WHERE model::text = ANY (ARRAY['account.account'::character varying::text, 'account.group'::character varying::text, 'account.tax'::character varying::text, 'account.fiscal.position'::character varying::text])
"ir_model_data_model_res_id_index" btree (model, res_id)
"ir_model_data_module_name_uniq_index" UNIQUE, btree (module, name)
"ir_model_data_name_idx2" gist (name gist_trgm_ops)
"ir_model_data_write_uid_idx" btree (write_uid) WHERE write_uid IS NOT NULL AND (write_uid <> ALL (ARRAY[1, 208196]))
Check constraints:
"ir_model_data_name_nospaces" CHECK (name::text !~~ '% %'::text)

> > Thanks in advance,
> >
> > Nicolas
>
>
>
> --
> Adrian Klaver
> adrian(dot)klaver(at)aklaver(dot)com