Disk Journal configuration

[rdomeracki]

Hello,

I need some journal tuning and i am interested in flush policy options:
#message_journal_flush_age = 1m
#message_journal_flush_interval = 1000000
#message_journal_segment_age = 1h
#message_journal_segment_size = 100mb
I can’t find explanation of the above in the documentation nor the config file.

[jochen]

These settings are virtually equivalent to the following Kafka settings (Graylog 2.x is using the Apache Kafka journal implementation under the hood):

https://kafka.apache.org/090/documentation.html#brokerconfigs

message_journal_flush_interval

flush.messages
This setting allows specifying an interval at which we will force an fsync of data written to the log. For example if this was set to 1 we would fsync after every message; if it were 5 we would fsync after every five messages. In general we recommend you not set this and use replication for durability and allow the operating system’s background flush capabilities as it is more efficient.

message_journal_flush_age

flush.ms
This setting allows specifying a time interval at which we will force an fsync of data written to the log. For example if this was set to 1000 we would fsync after 1000 ms had passed. In general we recommend you not set this and use replication for durability and allow the operating system’s background flush capabilities as it is more efficient.

message_journal_segment_age

segment.ms
This configuration controls the period of time after which Kafka will force the log to roll even if the segment file isn’t full to ensure that retention can delete or compact old data.

[rdomeracki]

Thank you for the answer.
So I think this parameters does not have significant impact on my Graylog journal.

Thanks again for the explanation.