Configuring:
Legacy Active Anti-Entropy
The configuration for the legacy AAE is kept in
the riak.conf configuration file.
Validate Settings
Once your configuration is set, you can verify its correctness by
running the riak command-line tool:
riak chkconfig
riak.conf Settings
Configurable parameters for Riak’s legacy active anti-entropy subsystem.
| Config | Description | Default |
|---|---|---|
anti_entropy |
How Riak will repair out-of-sync keys. If set to
active, out-of-sync keys will be repaired in the
background; if set to passive, out-of-sync keys are only
repaired on read; and if set to active-debug, verbose
debugging information will be output. |
active |
search.anti_entropy.throttle |
Whether the distributed throttle for Active Anti-Entropy is enabled. | on |
search.anti_entropy.throttle.$tier.solrq_queue_length |
Sets the throttling tiers for Active Anti-Entropy. Each tier is a
minimum vnode mailbox size and a time-delay that the throttle should
observe at that size and above. For example,
anti_entropy.throttle.tier1.delay = 0ms,
anti_entropy.throttle.tier2.mailbox_size = 40,
anti_entropy.throttle.tier2.delay = 5ms, etc. If
configured, there must be a tier which includes a mailbox size of 0.
Both .mailbox_size and .delay must be set for
each tier. |
|
search.anti_entropy.throttle.$tier.delay |
See the description for
anti_entropy.throttle.$tier.mailbox_size above. |
|
anti_entropy.bloomfilter |
Bloom filters are highly effective in shortcutting data queries that are destined to not find the requested key, though they tend to entail a small performance cost. | on |
anti_entropy.max_open_files |
20 |
|
anti_entropy.write_buffer_size |
The LevelDB options used by Active Anti-Entropy to generate the LevelDB-backed on-disk hashtrees. | 4MB |
anti_entropy.data_dir |
The directory where AAE hash trees are stored. | ./data/anti_entropy |
anti_entropy.trigger_interval |
The tick determines how often the Active Anti-Entropy manager looks for work to do (building/expiring trees, triggering exchanges, etc). Lowering this value will speed up the rate at which all replicas are synced across the cluster. Increasing the value is not recommended. | 15s |
anti_entropy.concurrency_limit |
Limit how many Active Anti-Entropy exchanges or builds can happen concurrently. | 2 |
anti_entropy.tree.expiry |
Determines how often hash trees are expired after being built. Periodically expiring a hash tree ensures that the on-disk hash tree data stays consistent with the actual K/V backend data. It also helps Riak identify silent disk failures and bit rot. However, expiration is not needed for normal active anti-entropy operations and should be infrequent for performance reasons. The time is specified in milliseconds. | 1w |
anti_entropy.tree.build_limit.per_timespan |
1h |
|
anti_entropy.tree.build_limit.number |
Restrict how fast AAE can build hash trees. Building the tree for a
given partition requires a full scan over that partition's data. Once
built, trees stay built until they are expired. .number is
the number of builds; .per_timespan is the amount of time
in which that number of builds occurs. |
1 |
anti_entropy.use_background_manager |
Whether AAE is to use a background process to limit AAE tree
rebuilds. If set to on, this will help to prevent system
response degradation under times of heavy load from multiple background
tasks that contend for the same system resources; setting this parameter
to off can cut down on system resource usage.
|
off |