# ERROR 2408 (HY000): ER\_COMPILATION\_TIMEOUT: Query compilation timed out and cannot be executed

> **📝 Note**: Please note, the full error text is `Query compilation timed out and cannot be executed... Set 'max_compilation_time_s' to equal or higher to try recompiling or 'interpreter_mode' session variable to 'mbc' or 'compile_lite' to only interpret the query and try running the query again.`

**Issue**

A query compilation timeout occurs when the `max_compilation_time_s` has been reached.  Once the compilation thread is killed, this error is issued to the client.  An error is printed to the tracelog: WARN: Compilation of query exceeded set flag time and was terminated: `query_text`.  Internally, the query will be marked with a kill flag.   If the same query is executed again, it will automatically and immediately fail successive execution attempts regardless if the query hits the `max_compilation_time_s` threshold again.

**Solutions**

* Clear the kill flag  by resetting  `max_compilation_time_s` to it's current or higher value on the master aggregator.
  ```sql
  SET GLOBAL max_compilation_time_s = 601;

  ```
  ```output

  Query OK, 0 rows affected (0.02 sec)

  ```
  ```sql
  SELECT @@max_compilation_time_s;

  ```
  ```output

  +--------------------------+
  | @@max_compilation_time_s |
  +--------------------------+
  |                      601 |
  +--------------------------+
  1 row in set (0.00 sec)
  ```
  > **📝 Note**: If an asynchronous compile limit is being reached, its worthwhile to investigate why and optionally increase the limit to be above the threshold of the queries that are triggering it.
* Set `interpreter_mode` session variable to `mbc` or `compile_lite`  so the query will interpret only.  Then try running the query again. 
  ```sql
  SET SESSION interpreter_mode = mbc;

  ```
  ```output

  Query OK, 0 rows affected (0.02 sec)

  ```
  ```sql
  SELECT @@interpreter_mode;

  ```
  ```output

  +--------------------+
  | @@interpreter_mode |
  +--------------------+
  |                mbc |
  +--------------------+
  1 row in set (0.00 sec)
  ```
  ```sql
  SET SESSION interpreter_mode = compile_lite;

  ```
  ```output

  Query OK, 0 rows affected (0.02 sec)
  ```
  ```sql
  SELECT @@interpreter_mode;

  ```
  ```output

  +--------------------+
  | @@interpreter_mode |
  +--------------------+
  |       compile_lite |
  +--------------------+
  1 row in set (0.00 sec)
  ```
* View the query plan to find out which parts of the query are taking the longest time to execute. Optimize that part of your query statement. See [EXPLAIN](https://docs.singlestore.com/db/v9.1/reference/sql-reference/data-manipulation-language-dml/explain.md), [PROFILE](https://docs.singlestore.com/db/v9.1/reference/sql-reference/data-manipulation-language-dml/profile.md), or [SingleStore Visual Explain](https://docs.singlestore.com/db/v9.1/query-data/query-tuning/singlestore-visual-explain.md) for more details.

***

Modified at: August 16, 2023

Source: [/db/v9.1/reference/troubleshooting-reference/query-errors/error-2408-hy-000-er-compilation-timeout-query-compilation-timed-out-and-cannot-be-executed/](https://docs.singlestore.com/db/v9.1/reference/troubleshooting-reference/query-errors/error-2408-hy-000-er-compilation-timeout-query-compilation-timed-out-and-cannot-be-executed/)

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