src/ceph/doc/dev/osd_internals/osd_throttles.txt

   1                                                                                                    Messenger throttle (number and size)
   2          |-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
   3                                                                      FileStore op_queue throttle (number and size, includes a soft throttle based on filestore_expected_throughput_(ops|bytes))
   4                                                                 |--------------------------------------------------------|
   5                                                                                                                                                                    WBThrottle
   6                                                                                                                        |---------------------------------------------------------------------------------------------------------|
   7                                                                                                                                                                  Journal (size, includes a soft throttle based on filestore_expected_throughput_bytes)
   8                                                                  |-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
   9                                                                                                                        |----------------------------------------------------------------------------------------------------> flushed ----------------> synced
  10                                                                                                                        |
  11 Op: Read Header --DispatchQ--> OSD::_dispatch --OpWQ--> PG::do_request --journalq--> Journal --FileStore::OpWQ--> Apply Thread --Finisher--> op_applied ------------------------------------------------------------->  Complete
  12                                               |                                                                                                                                                                      |
  13 SubOp:                                        --Messenger--> ReadHeader --DispatchQ--> OSD::_dispatch --OpWQ--> PG::do_request --journalq--> Journal --FileStore::OpWQ--> Apply Thread --Finisher--> sub_op_applied -
  14                                                                                                                                                                               |
  15                                                                                                                                                                               |-----------------------------> flushed ----------------> synced
  16                                                                                                                                                 |------------------------------------------------------------------------------------------|
  17                                                                                                                                                                                         Journal (size)
  18                                                                                                                                                                               |---------------------------------|
  19                                                                                                                                                                                         WBThrottle
  20                                                                                                                          |-----------------------------------------------------|
  21                                                                                                                             FileStore op_queue throttle (number and size)