Clickhouse: Can't start clickhouse 20.7.2.30 to centos7.5, last line in logs is "Will mlockall to prevent executable memory"

[levsion]

I install the 20.7.2.30 version from the rpm. When I start the clickhouse-server it cannot run, I get the log:

2020.09.02 17:16:35.859880 [ 25885 ] {} SentryWriter: Sending crash reports is disabled
2020.09.02 17:16:35.865925 [ 25885 ] {} Pipe: Pipe capacity is 1.00 MiB
2020.09.02 17:16:36.012988 [ 25885 ] {} : Starting ClickHouse 20.7.2.30 with revision 54437, no build id, PID 25885
2020.09.02 17:16:36.013097 [ 25885 ] {} Application: starting up
2020.09.02 17:16:36.026676 [ 25885 ] {} Application: Will mlockall to prevent executable memory from being paged out. It may take a few seconds

What does it mean???

[levsion]

I have send the crash log to : https://[email protected]/5226277

[den-crane]

Please run it in foreground and show stdout output

sudo -u clickhouse clickhouse-server --pid-file=/var/run/clickhouse-server/clickhouse-server.pid --config-file=/etc/clickhouse-server/config.xml

[filimonov]

Let me guess: you have a tiny VM? like VM in vagrant with 500 Mb of RAM by default?

ClickHouse enabled mlock_executable by default since 20.5 https://github.com/ClickHouse/ClickHouse/pull/11139

And the whole executable should now live in RAM, otherwise oomkiller will kill it during the attempt to mlock (check dmesg).

Please give more RAM to your VM, or add

<mlock_executable>false</mlock_executable>

to your clickhouse config.

[levsion]

Let me guess: you have a tiny VM? like VM in vagrant with 500 Mb of RAM by default?

ClickHouse enabled mlock_executable by default since 20.5 #11139

And the whole executable should now live in RAM, otherwise oomkiller will kill it during the attempt to mlock (check dmesg).

Please give more RAM to your VM, or add

<mlock_executable>false</mlock_executable>

to your clickhouse config.

Haha, yes, your guess is right！my linux server is google cloud with 1GB RAM and 2 core CPU, and it works well with version 20.3. then in the version20.7 i change the "mlock_executable" config to false, it works success !!! Thank you, you are so excellent.

[levsion]

Please run it in foreground and show stdout output

sudo -u clickhouse clickhouse-server --pid-file=/var/run/clickhouse-server/clickhouse-server.pid --config-file=/etc/clickhouse-server/config.xml

Thank you for your suggest. I have solve it by change the "mlock_executable" config to false. Thank you twice !!!

[filimonov]

(Added backward compatibility label, because you can't run clickhouse on the same machine with default config)