B.5.4.3 How MySQL Handles a Full Disk

This section describes how MySQL responds to disk-full errors (such as no space left on device), and to quota-exceeded errors (such as write failed or user block limit reached).

This section is relevant for writes to MyISAM tables. It also applies for writes to binary log files and binary log index file, except that references to row and record should be understood to mean event.

When a disk-full condition occurs, MySQL does the following:

To alleviate the problem, you can take the following actions:

Exceptions to the preceding behavior are when you use REPAIR TABLE or OPTIMIZE TABLE or when the indexes are created in a batch after LOAD DATA INFILE or after an ALTER TABLE statement. All of these statements may create large temporary files that, if left to themselves, would cause big problems for the rest of the system. If the disk becomes full while MySQL is doing any of these operations, it removes the big temporary files and mark the table as crashed. The exception is that for ALTER TABLE, the old table is left unchanged.