# InnoDB: Operating system error number 24 in a file operation... again

**URL:** <https://forums.percona.com/t/innodb-operating-system-error-number-24-in-a-file-operation-again/5914>\
**Category:** Percona XtraBackup\
**Created:** [October 4, 2017, 6:41am UTC](https://forums.percona.com/t/innodb-operating-system-error-number-24-in-a-file-operation-again/5914 "2017-10-04T06:41:48Z")\
**Posts on this page:** 2\
**Page:** 1

<div class="post-metadata">

**Author:** ![ast](https://avatars.discourse-cdn.com/v4/letter/a/858c86/32.png) [@ast](https://forums.percona.com/u/ast)\
**Post date:** [October 4, 2017, 6:41am UTC](https://forums.percona.com/t/innodb-operating-system-error-number-24-in-a-file-operation-again/5914/1 "2017-10-04T06:41:48Z")

</div>

Hi Guys.

Seen this asked before many times and have followed advice and guidance but at a complete loss with this. I have followed the settings to the letter as set out at [url][https://www.percona.com/blog/2016/12/28/using-percona-xtrabackup-mysql-instance-large-number-tables/[/url]](https://www.percona.com/blog/2016/12/28/using-percona-xtrabackup-mysql-instance-large-number-tables/%5B/url%5D)

Running ‘find /var/lib/mysql/ -name “\*.ibd” | wc -l’ returns 8338 so setting my limits of 2000000 seem really excessive.

my.cnf (have \*\*\*\* out the wsrep\_cluster\_address, wsrep\_sst\_auth and wsrep\_node\_address)

binlog\_format = ROW  
innodb\_buffer\_pool\_size = 2G  
innodb\_flush\_log\_at\_trx\_commit = 0  
innodb\_flush\_method = O\_DIRECT  
innodb\_log\_files\_in\_group = 2  
innodb\_log\_file\_size = 20M  
innodb\_file\_per\_table = 1  
transaction-isolation = READ-COMMITTED  
max\_connections = 100

wsrep\_cluster\_address = \*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*  
wsrep\_provider = /usr/lib64/libgalera\_smm.so  
wsrep\_sst\_auth = \*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*  
wsrep\_slave\_threads = 8  
wsrep\_cluster\_name = pptdrupalcluster  
wsrep\_node\_address = \*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*  
wsrep\_node\_name = Node2  
wsrep\_sst\_method = xtrabackup-v2  
default\_storage\_engine = InnoDB  
datadir = /var/lib/mysql  
open\_files\_limit = 2000000

log\_slave\_updates  
innodb\_locks\_unsafe\_for\_binlog = 1  
innodb\_autoinc\_lock\_mode = 2

[mysqld\_safe]  
pid-file = /run/mysqld/mysql.pid  
syslog

My systems open file hard limit is set to 2000000 as well.

Excerpt of /etc/security/limits.conf

mysql hard nofile 2000000  
mysql soft nofile 2000000

ulimit -a  
core file size (blocks, -c) 0  
data seg size (kbytes, -d) unlimited  
scheduling priority (-e) 0  
file size (blocks, -f) unlimited  
pending signals (-i) 31209  
max locked memory (kbytes, -l) 64  
max memory size (kbytes, -m) unlimited  
open files (-n) 1024  
pipe size (512 bytes, -p) 8  
POSIX message queues (bytes, -q) 819200  
real-time priority (-r) 0  
stack size (kbytes, -s) 8192  
cpu time (seconds, -t) unlimited  
max user processes (-u) 31209  
virtual memory (kbytes, -v) unlimited  
file locks (-x) unlimited

Is there something else I’m missing with this?

Thanks  
AST

---

<div class="post-metadata">

**Author:** ![mirfan](https://sea1.discourse-cdn.com/flex019/user_avatar/forums.percona.com/mirfan/32/16890_2.png) [@mirfan](https://forums.percona.com/u/mirfan)\
**Post date:** [October 5, 2017, 11:47pm UTC](https://forums.percona.com/t/innodb-operating-system-error-number-24-in-a-file-operation-again/5914/2 "2017-10-05T23:47:03Z")

</div>

This could be useful [url][Red Hat Customer Portal - Access to 24x7 support and knowledge](https://access.redhat.com/solutions/61334%5B/url%5D)  
Did you restarted mysql service after changing open-files-limit parameter value in my.cnf ?