This PR changes the retry of task actions to be a bit more aggressive
by reducing the maxWait. Current defaults were 1 min to 10 mins, which
lead to a very delayed recovery in case there are any transient network
issues between the overlord and the peons.
doc changes.
To bring consistency to docs and source this commit changes the default
values for maxRowsInMemory and rowFlushBoundary to 75000 after
discussion in PR https://github.com/druid-io/druid/pull/2457.
The previous default was 500000 and it's lower now on the grounds that
it's better for a default to be somewhat less efficient, and work,
than to reach for the stars and possibly result in
"OutOfMemoryError: java heap space" errors.
- Add druid.indexer.server.maxChatRequests, which sets up a QoSFilter on the main Jetty server.
- Deprecate druid.indexer.runner.separateIngestionEndpoint
- Deprecate druid.indexer.server.chathandler.*
Also extend description of the 'affinity' property of the worker strategy
fillCapacityWithAffinity and fix a couple typos of middle manager (to
be more consistent throughout the page).
Add additional verbiage about appropriate middle manager host value.
This is done by killing and respawning the jvms rather than reconnecting to existing
jvms, for a couple reasons. One is that it lets you restore tasks after server reboots
too, and another is that it lets you upgrade all the software on a box at once by just
restarting everything.
The main changes are,
1) Add "canRestore" and "stopGracefully" methods to Tasks that say if a task can
stop gracefully, and actually do a graceful stop. RealtimeIndexTask is the only
one that currently implements this.
2) Add "stop" method to TaskRunners that attempts to do an orderly shutdown.
ThreadPoolTaskRunner- call stopGracefully on restorable tasks, wait for exit
ForkingTaskRunner- close output stream to restorable tasks, wait for exit
RemoteTaskRunner- do nothing special, we actually don't want to shutdown
3) Add "restore" method to TaskRunners that attempts to bootstrap tasks from last run.
Only ForkingTaskRunner does anything here. It maintains a "restore.json" file with
a list of restorable tasks.
4) Have the CliPeon's ExecutorLifecycle lock the task base directory to avoid a restored
task and a zombie old task from stomping on each other.
this PR adds a JavaScriptWorkerSelectStrategy which allows defining
arbitrary logic for selecting workers to run task using a JavaScript
function.
This gives users full control to implement complex worker selection
strategies based on task attributes.
more tests and a complex javascript config
fix for java8 modify for nashorn compatibility