I want to turn off the redis persistence setting.

I use Redis 3.2.10.

Due to performance issues, I would like to process only memory instead of perpetuating it, but as stated in the configuration file documentation,

save"

is written and originally configured

# save9001 # save30010
# save 60 10000

is commenting out.
If you reboot in this state or check the status in redis-cli config get,

redis-cli config get save
1) "save"
2) "

is reflected in , but the file is written to the location set to dir and dbfilename .
How can I set the RDB file not to be written?

If you set the dir setting to a directory that does not have write permission, it will not be saved, but I think it is not a good condition because the log files are lined up with errors.
I also saw information that a failure to write an RDB file would increase the CPU load, but I couldn't see it in my environment.

Add based on the comments below
The exported file is the same as the one set to dbfilename in dump.rdb.
Also, if you set the dir setting to /var/lib/redis/ with write privileges, the persistent file will be written to this location.
AOF settings are

appendonly no
appendfilename "appendonly.aof"

However, appendonly.aof has not been created.

every 5 minutes if you set dir to a place where you do not have write permission, such as comment out or / Failed opening the RDB file dump.rdb(in server root dir/) for saving: Permission denied
An error appears in the log.

Repl-diskless-sync was no different whether it was yes or no.