[GitHub] regner commented on issue #1579: Autocompaction never triggered in Couch v2.2

[GitBox <gi...@apache.org>]

regner commented on issue #1579: Autocompaction never triggered in Couch v2.2
URL: https://github.com/apache/couchdb/issues/1579#issuecomment-424434230
 
 
   This is happening for us as well. We have roughly 400 GB of DB files and this hits us pretty hard as some of the DBs see a lot of changes.
   
   ![image](https://user-images.githubusercontent.com/815037/46030961-7551c080-c0ac-11e8-87d8-04cc035322f7.png)
   
   Our DB disk before the upgrade was hovering just below 60%. You can see the daily compaction (we have compaction restricted to off hours) take the disk space down a bit every day as it goes up. then on the night of September 6th we deployed CouchDB 2.2 and compaction just kinda stops happening. Disk space usage grew at a fairly steady pace and our alerts triggered at 85%.
   
   After a bunch of reviewing our configs, testing different configs, we were unable to get auto compaction to work. On the 23rd we ran a script that grabbed every DB, compared the disk size to data size, and then we manually compacted (using the _compact endpoint) the worst 1k DBs. This gave us back about 22% of our disk, but is not a long term solution.
   
   On one of our other DB servers that sees a lot of activity the _global_changes DB grew to about 85 GB in size. We manually triggered the compaction and it compacted down to 1 GB.
   
   We have been playing with a bunch of different values to see if something else works, but here are some of our current config settings:
   
   ```
   [compaction_daemon]
   check_interval = 3600
   min_file_size = 131072 (most our DBs are 500 MB in size)
   
   [compactions]
   _default = [{db_fragmentation, "40%"}, {view_fragmentation, "30%"}, {from, "03:00"}, {to, "09:00"}]
   ```
   
   We did confirm CouchDB is reading the compactions settings correctly and that the compaction daemon is running.
   
   We do configure CouchDB to store all data on the /srv mount, but there are no symlinks.
   
   If there is any other information you need or that we can provide let us know. :)

----------------------------------------------------------------
This is an automated message from the Apache Git Service.
To respond to the message, please log on GitHub and use the
URL above to go to the specific comment.
 
For queries about this service, please contact Infrastructure at:
users@infra.apache.org


With regards,
Apache Git Services