3.2. Base Configuration¶
3.2.1. Base CouchDB Options¶
- [couchdb]¶
- attachment_stream_buffer_size¶
Higher values may result in better read performance due to fewer read operations and/or more OS page cache hits. However, they can also increase overall response time for writes when there are many attachment write requests in parallel.
[couchdb] attachment_stream_buffer_size = 4096
- database_dir¶
Specifies location of CouchDB database files (
*.couch
named). This location should be writable and readable for the user the CouchDB service runs as (couchdb
by default).[couchdb] database_dir = /var/lib/couchdb
- default_security¶
Changed in version 3.0:
admin_only
is now the default.Default security object for databases if not explicitly set. When set to
everyone
, anyone can performs reads and writes. When set toadmin_only
, only admins can read and write. When set toadmin_local
, sharded databases can be read and written by anyone but the shards can only be read and written by admins.[couchdb] default_security = admin_only
- enable_database_recovery¶
Enable this to only “soft-delete” databases when DELETE /{db} DELETE requests are made. This will rename all shards of the database with a suffix of the form
<dbname>.YMD.HMS.deleted.couchdb
. You can then manually delete these files later, as desired.Default is
false
.[couchdb] enable_database_recovery = false
- file_compression¶
Changed in version 1.2: Added Google Snappy compression algorithm.
Method used to compress everything that is appended to database and view index files, except for attachments (see the
attachments
section). Available methods are:none
: no compressionsnappy
: use Google Snappy, a very fast compressor/decompressordeflate_N
: use zlib’s deflate;N
is the compression level which ranges from1
(fastest, lowest compression ratio) to9
(slowest, highest compression ratio)
[couchdb] file_compression = snappy
- maintenance_mode¶
A CouchDB node may be put into two distinct maintenance modes by setting this configuration parameter.
true
: The node will not respond to clustered requests from other nodes and the /_up endpoint will return a 404 response.nolb
: The /_up endpoint will return a 404 response.false
: The node responds normally, /_up returns a 200 response.
It is expected that the administrator has configured a load balancer in front of the CouchDB nodes in the cluster. This load balancer should use the /_up endpoint to determine whether or not to send HTTP requests to any particular node. For HAProxy, the following config is appropriate:
http-check disable-on-404 option httpchk GET /_up
- max_dbs_open¶
This option places an upper bound on the number of databases that can be open at once. CouchDB reference counts database accesses internally and will close idle databases as needed. Sometimes it is necessary to keep more than the default open at once, such as in deployments where many databases will be replicating continuously.
[couchdb] max_dbs_open = 100
- max_document_size¶
Changed in version 3.0.0.
Limit maximum document body size. Size is calculated based on the serialized Erlang representation of the JSON document body, because that reflects more accurately the amount of storage consumed on disk. In particular, this limit does not include attachments.
HTTP requests which create or update documents will fail with error code 413 if one or more documents is larger than this configuration value.
In case of
_update
handlers, document size is checked after the transformation and right before being inserted into the database.[couchdb] max_document_size = 8000000 ; bytes
Warning
Before version 2.1.0 this setting was implemented by simply checking http request body sizes. For individual document updates via PUT that approximation was close enough, however that is not the case for
_bulk_docs
endpoint. After 2.1.0 a separate configuration parameter was defined:chttpd/max_http_request_size
, which can be used to limit maximum http request sizes. After upgrade, it is advisable to review those settings and adjust them accordingly.
- os_process_timeout¶
If an external process, such as a query server or external process, runs for this amount of milliseconds without returning any results, it will be terminated. Keeping this value smaller ensures you get expedient errors, but you may want to tweak it for your specific needs.
[couchdb] os_process_timeout = 5000 ; 5 sec
- single_node¶
Added in version 3.0.0.
When this configuration setting is set to
true
, automatically create the system databases on startup. Must be setfalse
for a clustered CouchDB installation.
- uri_file¶
This file contains the full URI that can be used to access this instance of CouchDB. It is used to help discover the port CouchDB is running on (if it was set to
0
(e.g. automatically assigned any free one). This file should be writable and readable for the user that runs the CouchDB service (couchdb
by default).[couchdb] uri_file = /var/run/couchdb/couchdb.uri
- users_db_security_editable¶
Added in version 3.0.0.
When this configuration setting is set to
false
, reject any attempts to modify the_users
database security object. Modification of this object is deprecated in 3.x and will be completely disallowed in CouchDB 4.x.
- users_db_suffix¶
Specifies the suffix (last component of a name) of the system database for storing CouchDB users.
[couchdb] users_db_suffix = _users
Warning
If you change the database name, do not forget to remove or clean up the old database, since it will no longer be protected by CouchDB.
- util_driver_dir¶
Specifies location of binary drivers (icu, ejson, etc.). This location and its contents should be readable for the user that runs the CouchDB service.
[couchdb] util_driver_dir = /usr/lib/couchdb/erlang/lib/couch-1.5.0/priv/lib
- uuid¶
Added in version 1.3.
Unique identifier for this CouchDB cluster.
[couchdb] uuid = 0a959b9b8227188afc2ac26ccdf345a6
- view_index_dir¶
Specifies location of CouchDB view index files. This location should be writable and readable for the user that runs the CouchDB service (
couchdb
by default).[couchdb] view_index_dir = /var/lib/couchdb
- write_xxhash_checksums¶
Added in version 3.4.
The default value in version 3.4 is
false
. The legacy checksum algorithm will be used for writing couch_file blocks. During reads, both xxHash and the legacy checksum algorithm will be used to verify data integrity. In a future version of CouchDB the default value will becometrue
. However, it would still be possible to safely downgrade to version 3.4, which would be able to verify both xxHash and legacy checksums. If CouchDB version downgrade is not a concern, enabling xxHash checksums can result in a measuralbe document read performance, especially for larger document sizes:[couchdb] write_xxhash_checksums = false
- js_engine¶
Changed in version 3.4.
Select the default Javascript engine. Available options are
spidermonkey
andquickjs
. The default setting isspidermonkey
:[couchdb] js_engine = spidermonkey