ceph write amplification

[damo2929]

hi all

I have found some information about ceph write amplification and performance tuning here from the ceph site.
while it gives values it doesn't go into how to implement them.

the most important one am wanting to implement is bluestore_rocksdb_options

can somebody tell me where and how to set the value.
then do I need to recreate the OSD's for the values to take effect?

 

[spirit]

you just need to add them in /etc/ceph/ceph.conf

[osd]
bluestore_rocksdb_options = compression=kNoCompression,max_write_buffer_number=4,min_write_buffer_number_to_merge=1,recycle_log_file_num=4,write_buffer_size=268435456,writable_file_max_buffer_size=0,compaction_readahead_size=2097152,max_background_compactions=2,max_total_wal_size=1073741824

then restart the osd services. (no need to recreate)