Mirror of Apache CouchDB

Clone this repo:
  1. fe7f242 Remove folsom references. by Nick Vatamaniuc · 8 months ago main 2.1.4
  2. 961a5c8 Merge pull request #24 from apache/add-reshard-ioq-priority by Nick Vatamaniuc · 1 year, 4 months ago
  3. 33e8402 Add a proper reshard ioq class by Nick Vatamaniuc · 1 year, 4 months ago
  4. 6abecf9 Fix compiler warnings by Jay Doane · 1 year, 5 months ago
  5. f8661b6 Quiet noisy config tests by Jay Doane · 1 year, 5 months ago

IOQ classes

The following are the list of IOQ classes:

  • interactive
  • db_update
  • view_update
  • db_compact
  • view_compact
  • internal_repl
  • low

Bypassing IOQ

One can configure an ioq bypass, which removes an IO class from prioritization, as below:

config:set("ioq.bypass", "view_update", "true")

Note that setting an IOQ bypass can effectively trump all other classes, especially in the case of an interactive bypass v. compaction. This can lead to high disk usage.

Setting priorities

The priority for a class can also be set ala:

config:set("ioq", "compaction", "0.3")

Or globally, using snippet/rpc:

s:set_config("ioq", "compaction", "0.314", global)
rpc:multicall(config, set, ["ioq", "compaction", "0.217"])

As the interactive class is ‘everything else’ its priority cannot be directly set.