SQLite Memory Leak after 2.7.3 => 3.0.1 upgrade? #4976
Description
We upgraded ProxySQL from version 2.7.3 to 3.0.1 two weeks ago. We observe what seems to be a memory leak. The memory usage of ProxySQL is rising continously.
We didn't change any configuration when upgrading.
The memory seems to be increasing in the SQLite (sqlite3_memory_bytes metric) component.
Before the upgrade, the memory usage graph was more or less flat.
We do not use query caching.
ProxySQL version: 3.0.1
We are running ProxySQL as a container inside a GCP GKE Kubernetes cluster.
Using the official image from Dockerhub: https://hub.docker.com/r/proxysql/proxysql
OS version:
$ uname -a
Linux proxysql-74cd984b99-sksng 6.6.72+ #1 SMP PREEMPT_DYNAMIC Fri Apr 11 08:55:21 UTC 2025 x86_64 GNU/Linux
$ cat /etc/*release
PRETTY_NAME="Debian GNU/Linux 12 (bookworm)"
NAME="Debian GNU/Linux"
VERSION_ID="12"
VERSION="12 (bookworm)"
VERSION_CODENAME=bookworm
Configuration file:
datadir="/var/lib/proxysql"
admin_variables = {
admin_credentials="REDACTED",
stats_credentials="REDACTED"
read_only=false
mysql_ifaces="0.0.0.0:6032"
}
mysql_variables = {
threads=4
max_connections=2048
# 5 minutes in ms
default_query_timeout=300000
interfaces="0.0.0.0:6033;0.0.0.0:6034;0.0.0.0:6035;0.0.0.0:6036;0.0.0.0:6037;0.0.0.0:6038"
default_schema="information_schema"
server_version="8.0.20"
# 1.5s
connect_timeout_server=1500
# 3s
connect_timeout_server_max=3000
connect_retries_on_failure=1
monitor_username="REDACTED"
monitor_password="REDACTED"
# 600s
monitor_history=600000
# 5s
monitor_connect_interval=5000
# 1s
monitor_connect_timeout=1000
# 2s
monitor_ping_interval=2000
# 1.5s
monitor_read_only_interval=1500
# 800ms
monitor_read_only_timeout=800
# 10s
ping_interval_server_msec=10000
# 300ms
ping_timeout_server=300
}
mysql_servers = (
REDACTED
)
mysql_users = (
REDACTED
)
mysql_query_rules = (
{
rule_id=1
active=1
proxy_port=6034
destination_hostgroup=1
apply=1
},
{
rule_id=2
active=1
proxy_port=6033
destination_hostgroup=0
apply=1
},
{
rule_id=3
active=1
proxy_port=6035
destination_hostgroup=2
apply=1
},
{
rule_id=4
active=1
proxy_port=6037
destination_hostgroup=4
apply=1
},
{
rule_id=5
active=1
proxy_port=6036
destination_hostgroup=3
apply=1
},
{
rule_id=6
active=1
proxy_port=6038
destination_hostgroup=5
apply=1
}
)
mysql_replication_hostgroups = (
{
writer_hostgroup=0
reader_hostgroup=1
},
{
writer_hostgroup=3
reader_hostgroup=4
}
)