# Addressing the Maximum Table Memory Error

> **📝 Note**: SingleStore does not support setting the engine variables that are discussed in this topic.

If you see the error message below, the leaf at `'leafhost':leafport` has reached `maximum_table_memory`, which is the maximum cumulative memory in use by all tables on a node. SingleStore will not allow writes to any table once `maximum_table_memory` is reached (SingleStore will become read-only).

```
Leaf Error (leafhost:leafport): Memory usage by SingleStore for tables (##### MB) has reached the value of 'maximum_table_memory' global variable (##### MB). This query cannot be executed.

```

You can resolve this issue with the steps below.

## Check for Data Skew

First, determine which nodes are reaching their memory capacity. Do this by checking for [data skew](https://docs.singlestore.com/db/v9.1/create-a-database/detecting-and-resolving-data-skew.md) across your nodes. The data skew topic discusses how to address data skew, if it is present.

## If Data Skew Is not Present

If nodes are reaching `maximum_table_memory` without skew, the cluster itself is nearing maximum memory capacity. To resolve this, you need to add capacity or delete data. To add capacity, see [Administering a Cluster](https://docs.singlestore.com/db/v9.1/user-and-cluster-administration/maintain-your-cluster/administering-a-cluster.md). If additional leaf nodes are not available, use the instructions below to delete data in batches. `DELETE` queries use 50 bytes of memory per record deleted until the `DELETE` commits, so the `maximum_table_memory` needs to be temporarily increased on all nodes during the `DELETE`.

On each leaf node in your cluster, do the following:

1. Pause write workloads from an aggregator or your application.

2. Check current `maximum_memory` and `maximum_table_memory`.
   ```sql
   select @@global.maximum_memory

   ```
   ```output

   +-------------------------+
   | @@global.maximum_memory |
   +-------------------------+
   |                   65536 |
   +-------------------------+
   1 row in set (0.00 sec)

   ```
   ```sql
   select @@global.maximum_table_memory
   +-------------------------------+
   | @@global.maximum_table_memory |
   +-------------------------------+
   |                         57927 |
   +-------------------------------+
   1 row in set (0.00 sec)
   ```

3. Increase `maximum_table_memory` to 95% of `maximum_memory`. The default value is 90% of `maximum_memory`.
   ```sql
   set @@global.maximum_table_memory=62259;

   ```
   ```output

   Query OK, 0 rows affected (0.00 sec)

   ```

4. Execute small batches of DELETE queries. Limit to 100,000 records or less to reduce memory used until commit.
   ```sql
   DELETE FROM mytable limit 100000;

   ```
   ```output

   Query OK, 0 rows affected (1.64 sec)

   ```

5. Restore `maximum_table_memory` to original value.
   ```sql
   set @@global.maximum_table_memory=57927;

   ```
   ```output

   Query OK, 0 rows affected (0.00 sec)

   ```

***

Modified at: April 26, 2023

Source: [/db/v9.1/user-and-cluster-administration/maintain-your-cluster/managing-memory/addressing-the-maximum-table-memory-error/](https://docs.singlestore.com/db/v9.1/user-and-cluster-administration/maintain-your-cluster/managing-memory/addressing-the-maximum-table-memory-error/)

(An index of the documentation is available at /llms.txt)