vtctl Throttler Command Reference

The following vtctl commands are available for controlling the tablet throttler

Commands #

UpdateThrottlerConfig #

Update tablet throttler configuration for all tablets of a given keyspace.

Usage #

UpdateThrottlerConfig -- [--enable|--disable] [--threshold=<float64>] [--custom-query=<query>] [--check-as-check-self|--check-as-check-shard] [--throttle-app|unthrottle-app=<name>] [--throttle-app-ratio=<float, range [0..1]>] [--throttle-app-duration=<duration>] <keyspace>

Examples #

UpdateThrottlerConfig -- --enable --threshold "3.0" commerce

UpdateThrottlerConfig -- --disable commerce

UpdateThrottlerConfig -- --throttle-app="vreplication" --throttle-app-ratio=0.5 --throttle-app-duration="30m" commerce

UpdateThrottlerConfig -- --unthrottle-app="vreplication" commerce

Flags #

enableBooleanenable the throttler. Once enabled, the throttler probes the MySQL servers for metrics, and responds to check requests according to those metrics
disableBooleandisables the throttler. Once disabled, the throttler responds to all check requests with 200 OK. It will not probe the MySQL servers for metrics
thresholdDoubleset a new threshold. Unless specified otherwise, the throttler measures replication lag by querying for heartbeat values, and the threshold stands for seconds of lag (i.e. the value 2.5 stands for two and a half seconds)
custom-queryStringoverride the default replication lag measurement, and suggest a different query. Valid values are:
- empty, meaning the throttler should use the default replication lag query
- A SELECT that returns a single line, single column, floating point value
check-as-check-shardBooleanthis is the default behavior. A /throttler/check request checks the shard health. When using the default replication lag query, this is the desired check: the primary tablet's throttler responds by evaluating the overall lag throughout the shard/replicas
check-as-check-selfBooleanoverride default behavior, and this can be useful when a --custom-query is set. A /throttler/check request will only consider the tablet's own metrics, and not the overall shard metrics

Arguments #

  • <keyspace> – Required. The keyspace for which to apply the throttler configuration. All tablets in all shards and cells assigned to this keyspace are affected.

Errors #

Any error transporting the configuration to a cell's local topo server.

See Also #

vtctl Throttler Command Reference