Unable to consume items

[tlf30]

Please verify that this bug has NOT been raised before.

• I checked and didn't find a similar issue

Describe the bug*

When completing a build order, the allocated stock was not consumed.
I re-opened the build order and tried to manually consume the allocated stock. Only a couple line items got consumed.
No errors are being thrown.

2026-03-11.14-16-36.mp4

Steps to Reproduce

1. Start a build order
2. Allocate parts
3. Start incomplete parts
4. Complete parts
5. The allocated stock will not automatically become consumed.
6. Attempt to consume the stock manually.
7. Only some stock will get consumed. Sometimes trying multiple times can get another couple line items.

Expected behaviour

When a part is completed, it is assumed the stock will be consumed.

Deployment Method

Package

Version Information

InvenTree-Version: 1.2.3
Django Version: 5.2.11
Commit Hash: 12da3b0
Commit Date: 2026-02-22T12:25:31Z
Commit Branch: 1.2.x stable
Database: django.db.backends.sqlite3
Debug-Mode: False
Deployed using Docker: False
Platform: Linux-6.8.0-101-generic-x86_64-with-glibc2.39
Installer: PKG
Target: ubuntu:24.04
Active plugins: [{"name":"InvenTreeBarcode","slug":"inventreebarcode","version":"2.1.0"},{"name":"BOM Exporter","slug":"bom-exporter","version":"1.1.0"},{"name":"InvenTree Exporter","slug":"inventree-exporter","version":"1.0.0"},{"name":"Parameter Exporter","slug":"parameter-exporter","version":"2.0.0"},{"name":"InvenTreeEmailNotifications","slug":"inventree-email-notification","version":"1.0.0"},{"name":"InvenTreeUINotifications","slug":"inventree-ui-notification","version":"1.0.0"},{"name":"InvenTreeCurrencyExchange","slug":"inventreecurrencyexchange","version":"1.0.0"},{"name":"InvenTreeMachines","slug":"inventree-machines","version":"1.0.0"},{"name":"InvenTreeLabel","slug":"inventreelabel","version":"1.1.0"},{"name":"InvenTreeLabelMachine","slug":"inventreelabelmachine","version":"1.0.0"},{"name":"InvenTreeLabelSheet","slug":"inventreelabelsheet","version":"1.0.1"},{"name":"DigiKeyBarcodePlugin","slug":"digikeyplugin","version":"1.0.1"},{"name":"LCSCBarcodePlugin","slug":"lcscplugin","version":"1.0.1"},{"name":"MouserBarcodePlugin","slug":"mouserplugin","version":"1.0.1"},{"name":"TMEBarcodePlugin","slug":"tmeplugin","version":"1.0.1"}]

Try to reproduce on the demo site

I did not try to reproduce

Is the bug reproducible on the demo site?

Not reproducible

Relevant log output

[SchrodingersGat]

@tlf30 that's a strange one.

Can you please navigate to the "Admin Center" and see if there are any failed tasks:

[tlf30]

Oh, yes there are a LOT of errors...
build.tasks.consume_build_item

database is locked : Traceback (most recent call last):
File "/opt/inventree/env/lib/python3.12/site-packages/django/db/backends/utils.py", line 105, in _execute
return self.cursor.execute(sql, params)
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/opt/inventree/env/lib/python3.12/site-packages/django/db/backends/sqlite3/base.py", line 360, in execute
return super().execute(query, params)
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
sqlite3.OperationalError: database is locked
The above exception was the direct cause of the following exception:
Traceback (most recent call last):
File "/opt/inventree/env/lib/python3.12/site-packages/django_q/worker.py", line 103, in worker
res = f(*task["args"], **task["kwargs"])
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/usr/lib/python3.12/contextlib.py", line 81, in inner
return func(*args, **kwds)
^^^^^^^^^^^^^^^^^^^
File "/opt/inventree/src/backend/InvenTree/build/tasks.py", line 58, in consume_build_item
item.complete_allocation(
File "/usr/lib/python3.12/contextlib.py", line 81, in inner
return func(*args, **kwds)
^^^^^^^^^^^^^^^^^^^
File "/opt/inventree/src/backend/InvenTree/build/models.py", line 1941, in complete_allocation
item = item.splitStock(quantity, None, user, notes=notes)
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/usr/lib/python3.12/contextlib.py", line 81, in inner
return func(*args, **kwds)
^^^^^^^^^^^^^^^^^^^
File "/opt/inventree/src/backend/InvenTree/stock/models.py", line 2328, in splitStock
new_stock.save(add_note=False)
File "/opt/inventree/src/backend/InvenTree/stock/models.py", line 829, in save
super().save(*args, **kwargs)
File "/opt/inventree/src/backend/InvenTree/InvenTree/models.py", line 130, in save
super().save(*args, **kwargs)
File "/opt/inventree/src/backend/InvenTree/generic/states/states.py", line 295, in save
super().save(*args, **kwargs)
File "/opt/inventree/src/backend/InvenTree/InvenTree/models.py", line 179, in save
super().save(force_insert=force_insert, force_update=force_update, **kwargs)
File "/opt/inventree/src/backend/InvenTree/InvenTree/models.py", line 898, in save
super().save(*args, **kwargs)
File "/opt/inventree/env/lib/python3.12/site-packages/mptt/models.py", line 1105, in save
super().save(*args, **kwargs)
File "/opt/inventree/env/lib/python3.12/site-packages/django/db/models/base.py", line 902, in save
self.save_base(
File "/opt/inventree/env/lib/python3.12/site-packages/django/db/models/base.py", line 1008, in save_base
updated = self._save_table(
^^^^^^^^^^^^^^^^^
File "/opt/inventree/env/lib/python3.12/site-packages/django/db/models/base.py", line 1169, in _save_table
results = self._do_insert(
^^^^^^^^^^^^^^^^
File "/opt/inventree/env/lib/python3.12/site-packages/django/db/models/base.py", line 1210, in _do_insert
return manager._insert(
^^^^^^^^^^^^^^^^
File "/opt/inventree/env/lib/python3.12/site-packages/django/db/models/manager.py", line 87, in manager_method
return getattr(self.get_queryset(), name)(*args, **kwargs)
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/opt/inventree/env/lib/python3.12/site-packages/django/db/models/query.py", line 1873, in _insert
return query.get_compiler(using=using).execute_sql(returning_fields)
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/opt/inventree/env/lib/python3.12/site-packages/django/db/models/sql/compiler.py", line 1882, in execute_sql
cursor.execute(sql, params)
File "/opt/inventree/env/lib/python3.12/site-packages/django/db/backends/utils.py", line 79, in execute
return self._execute_with_wrappers(
^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/opt/inventree/env/lib/python3.12/site-packages/django/db/backends/utils.py", line 92, in _execute_with_wrappers
return executor(sql, params, many, context)
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/opt/inventree/env/lib/python3.12/site-packages/django/db/backends/utils.py", line 100, in _execute
with self.db.wrap_database_errors:
File "/opt/inventree/env/lib/python3.12/site-packages/django/db/utils.py", line 91, in __exit__
raise dj_exc_value.with_traceback(traceback) from exc_value
File "/opt/inventree/env/lib/python3.12/site-packages/django/db/backends/utils.py", line 105, in _execute
return self.cursor.execute(sql, params)
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/opt/inventree/env/lib/python3.12/site-packages/django/db/backends/sqlite3/base.py", line 360, in execute
return super().execute(query, params)
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
django.db.utils.OperationalError: database is locked

build.tasks.consume_build_item

{'location': ['Stock items cannot be located into structural stock locations!']} : Traceback (most recent call last):
File "/opt/inventree/env/lib/python3.12/site-packages/django_q/worker.py", line 103, in worker
res = f(*task["args"], **task["kwargs"])
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/usr/lib/python3.12/contextlib.py", line 81, in inner
return func(*args, **kwds)
^^^^^^^^^^^^^^^^^^^
File "/opt/inventree/src/backend/InvenTree/build/tasks.py", line 58, in consume_build_item
item.complete_allocation(
File "/usr/lib/python3.12/contextlib.py", line 81, in inner
return func(*args, **kwds)
^^^^^^^^^^^^^^^^^^^
File "/opt/inventree/src/backend/InvenTree/build/models.py", line 1941, in complete_allocation
item = item.splitStock(quantity, None, user, notes=notes)
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/usr/lib/python3.12/contextlib.py", line 81, in inner
return func(*args, **kwds)
^^^^^^^^^^^^^^^^^^^
File "/opt/inventree/src/backend/InvenTree/stock/models.py", line 2328, in splitStock
new_stock.save(add_note=False)
File "/opt/inventree/src/backend/InvenTree/stock/models.py", line 776, in save
self.clean()
File "/opt/inventree/src/backend/InvenTree/stock/models.py", line 904, in clean
raise ValidationError({
django.core.exceptions.ValidationError: {'location': ['Stock items cannot be located into structural stock locations!']}

build.tasks.consume_build_item

{'location': ['Stock items cannot be located into structural stock locations!']} : Traceback (most recent call last):
File "/opt/inventree/env/lib/python3.12/site-packages/django_q/worker.py", line 103, in worker
res = f(*task["args"], **task["kwargs"])
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/usr/lib/python3.12/contextlib.py", line 81, in inner
return func(*args, **kwds)
^^^^^^^^^^^^^^^^^^^
File "/opt/inventree/src/backend/InvenTree/build/tasks.py", line 58, in consume_build_item
item.complete_allocation(
File "/usr/lib/python3.12/contextlib.py", line 81, in inner
return func(*args, **kwds)
^^^^^^^^^^^^^^^^^^^
File "/opt/inventree/src/backend/InvenTree/build/models.py", line 1941, in complete_allocation
item = item.splitStock(quantity, None, user, notes=notes)
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/usr/lib/python3.12/contextlib.py", line 81, in inner
return func(*args, **kwds)
^^^^^^^^^^^^^^^^^^^
File "/opt/inventree/src/backend/InvenTree/stock/models.py", line 2328, in splitStock
new_stock.save(add_note=False)
File "/opt/inventree/src/backend/InvenTree/stock/models.py", line 776, in save
self.clean()
File "/opt/inventree/src/backend/InvenTree/stock/models.py", line 904, in clean
raise ValidationError({
django.core.exceptions.ValidationError: {'location': ['Stock items cannot be located into structural stock locations!']}

Based on these, I'm guessing that somehow stock got assigned to the wrong place. I'll check.

[tlf30]

So stock was received into the warehouse top structural location.
As a quick fix I have flagged that stock location as not structural.
Now when I retry, the tasks to consume the item just stay pending.
A bunch more errors popped in, for the database being locked.

Error Details
database is locked : Traceback (most recent call last):
File "/opt/inventree/env/lib/python3.12/site-packages/django/db/backends/utils.py", line 105, in _execute
return self.cursor.execute(sql, params)
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/opt/inventree/env/lib/python3.12/site-packages/django/db/backends/sqlite3/base.py", line 360, in execute
return super().execute(query, params)
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
sqlite3.OperationalError: database is locked
The above exception was the direct cause of the following exception:
Traceback (most recent call last):
File "/opt/inventree/env/lib/python3.12/site-packages/django_q/worker.py", line 103, in worker
res = f(*task["args"], **task["kwargs"])
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/usr/lib/python3.12/contextlib.py", line 81, in inner
return func(*args, **kwds)
^^^^^^^^^^^^^^^^^^^
File "/opt/inventree/src/backend/InvenTree/build/tasks.py", line 80, in consume_build_line
item.complete_allocation(
File "/usr/lib/python3.12/contextlib.py", line 81, in inner
return func(*args, **kwds)
^^^^^^^^^^^^^^^^^^^
File "/opt/inventree/src/backend/InvenTree/build/models.py", line 1941, in complete_allocation
item = item.splitStock(quantity, None, user, notes=notes)
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/usr/lib/python3.12/contextlib.py", line 81, in inner
return func(*args, **kwds)
^^^^^^^^^^^^^^^^^^^
File "/opt/inventree/src/backend/InvenTree/stock/models.py", line 2328, in splitStock
new_stock.save(add_note=False)
File "/opt/inventree/src/backend/InvenTree/stock/models.py", line 829, in save
super().save(*args, **kwargs)
File "/opt/inventree/src/backend/InvenTree/InvenTree/models.py", line 130, in save
super().save(*args, **kwargs)
File "/opt/inventree/src/backend/InvenTree/generic/states/states.py", line 295, in save
super().save(*args, **kwargs)
File "/opt/inventree/src/backend/InvenTree/InvenTree/models.py", line 179, in save
super().save(force_insert=force_insert, force_update=force_update, **kwargs)
File "/opt/inventree/src/backend/InvenTree/InvenTree/models.py", line 898, in save
super().save(*args, **kwargs)
File "/opt/inventree/env/lib/python3.12/site-packages/mptt/models.py", line 1105, in save
super().save(*args, **kwargs)
File "/opt/inventree/env/lib/python3.12/site-packages/django/db/models/base.py", line 902, in save
self.save_base(
File "/opt/inventree/env/lib/python3.12/site-packages/django/db/models/base.py", line 1008, in save_base
updated = self._save_table(
^^^^^^^^^^^^^^^^^
File "/opt/inventree/env/lib/python3.12/site-packages/django/db/models/base.py", line 1169, in _save_table
results = self._do_insert(
^^^^^^^^^^^^^^^^
File "/opt/inventree/env/lib/python3.12/site-packages/django/db/models/base.py", line 1210, in _do_insert
return manager._insert(
^^^^^^^^^^^^^^^^
File "/opt/inventree/env/lib/python3.12/site-packages/django/db/models/manager.py", line 87, in manager_method
return getattr(self.get_queryset(), name)(*args, **kwargs)
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/opt/inventree/env/lib/python3.12/site-packages/django/db/models/query.py", line 1873, in _insert
return query.get_compiler(using=using).execute_sql(returning_fields)
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/opt/inventree/env/lib/python3.12/site-packages/django/db/models/sql/compiler.py", line 1882, in execute_sql
cursor.execute(sql, params)
File "/opt/inventree/env/lib/python3.12/site-packages/django/db/backends/utils.py", line 79, in execute
return self._execute_with_wrappers(
^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/opt/inventree/env/lib/python3.12/site-packages/django/db/backends/utils.py", line 92, in _execute_with_wrappers
return executor(sql, params, many, context)
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/opt/inventree/env/lib/python3.12/site-packages/django/db/backends/utils.py", line 100, in _execute
with self.db.wrap_database_errors:
File "/opt/inventree/env/lib/python3.12/site-packages/django/db/utils.py", line 91, in __exit__
raise dj_exc_value.with_traceback(traceback) from exc_value
File "/opt/inventree/env/lib/python3.12/site-packages/django/db/backends/utils.py", line 105, in _execute
return self.cursor.execute(sql, params)
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/opt/inventree/env/lib/python3.12/site-packages/django/db/backends/sqlite3/base.py", line 360, in execute
return super().execute(query, params)
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
django.db.utils.OperationalError: database is locked

EDIT:
So after waiting a bit, a few more line items were consumed. Most still are not. There are no more scheduled tasks listed.

[SchrodingersGat]

There are no more scheduled tasks listed.

What about failed tasks? I expect there should be some failed tasks with "Attempts = 5"?

This looks like a similar issue to one I have been looking into, with a potential "solution" incoming in #11500

In particular, when you "consume" items against a build, this task is offloaded to the background worker - as it can be quite time consuming and block / timeout the web connection.

However, there are some concurrency limitations when running a sqlite database - which does not handle multiple connections as well as other database backends (e.g. postgres).

The background worker is crashing because it sees the database as locked. Hopefully the linked PR will improve the reliability here, but the most robust solution would be to switch to a more reliable database backend (such as postgres).

---

That being said, we have supported sqlite for years now without seeing this issue - and now within two days there has been this issue and also a very similar one with completing sales order shipments (which is a very analogous process).

[tlf30]

Yes, I have a lot of tasks with 5 failed attempts. I gave it a couple days to settle, they never were able to complete.

I use SQLite in quite a few of my own apps, and also have never seen this issue.
Is there an easy way to migrate the database contents to postgres? I'm going to assume that it will also help performance. The server has 8 cores and 16GB of ram. It uses just a couple percent CPU and usually around 3 GB of the ram, yet is incredibly slow. The storage is a SSD raid 6, very fast.

[SchrodingersGat]

Digging deeper into this I have found some more contributing factors. When consuming multiple lines or items, each consumption task is split into a separate task for the background worker - which can overwhelm the worker which is already limited by the existing sqlite performance issues. I will submit a patch to improve the build order consumption process.

[SchrodingersGat]

Larger discussion of the underlying issues here - #11528

[tlf30]

I can confirm that this issue is not present on postgres