The server cannot open a required file because the operating system or MySQL has exhausted file handles or disk resources.
MySQL Error 23: EE_OUT_OF_FILERESOURCES means the server hit its file descriptor or disk quota limits and cannot open the requested table or log file. Raise OS and MySQL open file limits, close unused tables, or free disk space to resolve the problem.
Out of resources when opening file '%s' (OS errno %d - %s)
MySQL raises error 23 with condition EE_OUT_OF_FILERESOURCES when it tries to open a table, index, log, or temporary file but the operating system refuses because required resources are exhausted.<\/p>
The error text Out of resources when opening file '%s' (OS errno %d) signals that the server ran out of file descriptors, inodes, or disk space.
Until resources are freed or limits are raised, affected SQL statements fail.<\/p>
Excessive concurrent table activity forces MySQL to exceed the open_files_limit or the global table_open_cache, triggering the OS soft limit on file descriptors.<\/p>
Low ulimit -n settings, full disks, or depleted inodes also block new file handles.
Heavy temporary table use in complex queries can exhaust resources quickly.<\/p>
Start by checking available file descriptors with lsof or cat /proc/sys/fs/file-nr, then compare to ulimit -n and MySQL open_files_limit. Increase both if close to capacity.<\/p>
Verify free disk space and inode counts with df -h and df -i, then clean logs or move data to larger volumes.
Restart MySQL after adjusting limits to apply changes.<\/p>
On busy OLTP servers, thousands of hot tables remain open. Raising table_open_cache and open_files_limit together with innodb_open_files keeps performance stable while preventing the error.<\/p>
During large ETL jobs, temporary tables balloon. Setting tmp_table_size and max_heap_table_size appropriately or directing tmpdir to a spacious SSD avoids resource exhaustion.<\/p>
Monitor file descriptor usage with Prometheus or Percona Monitoring and tweak limits before saturation.
Implement log rotation and purge binary logs with PURGE BINARY LOGS regularly.<\/p>
Galaxy’s modern SQL editor highlights failing queries instantly and lets teams endorse optimized versions, reducing runaway temp table creation that can trigger EE_OUT_OF_FILERESOURCES.<\/p>
Error 24 Too many open files in system occurs when the OS limit is lower than requested, fixed by raising fs.file-max. Error 1021 Disk full triggers similar troubleshooting steps but focuses on storage size instead of descriptors.<\/p>.
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