# PXC 5.6 Memory leak?

**URL:** <https://forums.percona.com/t/pxc-5-6-memory-leak/5975>\
**Category:** Percona XtraDB Cluster 5.x\
**Created:** [November 3, 2017, 8:11am UTC](https://forums.percona.com/t/pxc-5-6-memory-leak/5975 "2017-11-03T08:11:59Z")\
**Posts on this page:** 1\
**Page:** 1

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**Author:** ![matteraf](https://avatars.discourse-cdn.com/v4/letter/m/4da419/32.png) [@matteraf](https://forums.percona.com/u/matteraf)\
**Post date:** [November 3, 2017, 8:11am UTC](https://forums.percona.com/t/pxc-5-6-memory-leak/5975/1 "2017-11-03T08:11:59Z")

</div>

Hi, we have a 5-node cluster

Server version: 5.6.34-79.1-56-log Percona XtraDB Cluster (GPL), Release rel79.1, Revision 7c38350, WSREP version 26.19, wsrep\_26.19

All members uses memory and it seems not to be release them, so we have to restart database sometimes.

In particular (the easiest to analyze), we have one node with few or none connections, and uses memory, and never release.

Server config

Linux: Linux version 2.6.32-642.11.1.el6.x86\_64 (mockbuild@c1bm.rdu2.centos.org)  
Build: (gcc version 4.4.7 20120313 (Red Hat 4.4.7-17) (GCC) )  
Release : 2.6.32-642.11.1.el6.x86\_64  
Version : #1 SMP Fri Nov 18 19:25:05 UTC 2016  
cpuinfo: model name : Intel(R) Xeon(R) CPU E5506 @ 2.13GHz  
cpuinfo: vendor\_id : GenuineIntel  
cpuinfo: microcode : 21  
cpuinfo: cpuid level : 11

Memory Stats ──────────────────────────────────────────────  
RAM High Low Swap  
Total MB 7856.8 -0.0 -0.0 8000.0  
Free MB 6287.8 -0.0 -0.0 7277.9  
Free Percent 80.0% 100.0% 100.0% 91.0%  
MB MB MB  
Cached= 579.8 Active= 883.9  
Buffers= 147.5 Swapcached= 6.7 Inactive = 397.9  
Dirty = 2.3 Writeback = 0.0 Mapped = 211.7  
Slab = 97.2 Commit\_AS = 5285.5 PageTables= 24.4

/etc/my.cnf (node with less or none connections)

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

[mysqld]  
user = mysql  
port = 3306  
socket = /var/lib/mysql/mysql.sock  
pid-file = /var/run/mysql/mysql.pid  
log-error = /var/log/mysql/mysql.err  
datadir = /mysql/data  
expire\_logs\_days = 2

gtid\_mode = ON  
enforce-gtid-consistency = 1  
server-id = 5  
#thread\_handling = pool-of-threads  
#thread\_pool\_idle\_timeout = 60  
#thread\_pool\_high\_prio\_mode = transactions  
#thread\_pool\_max\_threads = 3000  
#thread\_pool\_size = 4  
#extra\_port = 3307  
#extra\_max\_connections = 2

max\_connections = 10000  
max\_connect\_errors = 99999  
max\_allowed\_packet = 16M  
skip-host-cache  
skip-name-resolve

explicit\_defaults\_for\_timestamp = 1  
performance\_schema = off  
#thread\_statistics = on  
#userstat = on  
#query\_response\_time\_stats = on

transaction\_isolation = READ-COMMITTED  
log-bin = /mysql/binlog/mysql-bin  
slow\_query\_log = 0  
log\_output = FILE  
long\_query\_time = 5  
event\_scheduler = ON  
innodb\_undo\_tablespaces = 3  
innodb\_undo\_directory = /mysql/undo

# \*\*\* INNODB Specific options \*\*\*

innodb\_buffer\_pool\_size = 2G  
innodb\_data\_file\_path = ibdata1:256M:autoextend  
innodb\_thread\_concurrency = 16  
innodb\_log\_file\_size = 256M  
innodb\_log\_files\_in\_group = 3  
innodb\_file\_per\_table

# \*\*\* Galera Cluster Settings \*\*\*

binlog\_format = ROW  
default-storage-engine = innodb  
innodb\_autoinc\_lock\_mode = 2  
log\_slave\_updates  
query\_cache\_size = 0  
query\_cache\_type = 0

# wsrep Provider Settings

wsrep\_provider = /usr/lib64/galera3/libgalera\_smm.so  
wsrep\_provider\_options = “gcache.size=8G;gcache.page\_size=128M;cert.log\_conflicts=ON;gcs.fc\_limit=32”  
wsrep\_cluster\_address = “gcomm://server-05,server-04,server-03,server-02,server-01”  
wsrep\_cluster\_name = “server”  
wsrep\_node\_address = “10.1.3.225”  
wsrep\_node\_name = “server-05”  
wsrep\_sst\_method = xtrabackup-v2  
wsrep\_sst\_auth = “sstuser:despegar#mysql”  
wsrep\_node\_incoming\_address = “server-01:33033”  
wsrep\_slave\_threads = 8  
wsrep\_notify\_cmd = galeranotify.py  
wsrep\_sst\_donor = server-05,server-04,server-03,server-02,server-01  
wsrep\_log\_conflicts = ON  
[sst]  
progress = 1  
time = 1

We want to know why happen this.

Thanks in advance,

Fernando.