Druid relies on the page cache of Linux in order to have memory segments.
However when loading segments from deep storage or rebalancing the page
cache can get poisoned by segments that should not be in memory yet.
This can significantly slow down Druid in case rebalancing happens
as data that might not be queried often is suddenly in the page cache.
This PR implements the same logic as is in Apache Cassandra and Apache
Bookkeeper.
Closes#4746
* use reflection to call hadoop fs.rename to workaround different hadoop jar version in main and hdfs-storage extension class loader
* find rename method recursively
* Deduplicate DataSegments contents (loadSpec's keys, dimensions and metrics lists as a whole) more aggressively; use ArrayMap instead of default LinkedHashMap for DataSegment.loadSpec, because they have only 3 entries on average; prune DataSegment.loadSpec on brokers
* Fix DataSegmentTest
* Refinements
* Try to fix
* Fix the second DataSegmentTest
* Nullability
* Fix tests
* Fix tests, unify to use TestHelper.getJsonMapper()
* Revert TestUtil as ServerTestHelper, fix tests
* Add newline
* Fix indexing tests
* Fix s3 tests
* Try to fix tests, remove lazy caching of ObjectMapper in TestHelper, rename TestHelper.getJsonMapper() to makeJsonMapper()
* Fix HDFS tests
* Fix HdfsDataSegmentPusherTest
* Capitalize constant names
* Avoid usages of Default system Locale and printing to System.out or System.err in production code
* Fix Charset in DruidKerberosUtil
* Remove redundant string format in GenericIndexed
* Rename StringUtils.safeFormat() to unimportantSafeFormat(); add StringUtils.format() which fails as well as String.format()
* Fix testSafeFormat()
* More fixes of redundant StringUtils.format() inside ISE
* Rename unimportantSafeFormat() to nonStrictFormat()
* Make using implicit system charset an error
* Use StringUtils.toUtf8() and fromUtf8() instead of String.getBytes() and new String()
* Use English locale in StringUtils.safeFormat()
* Restore comment
* Adding s3a schema and s3a implem to hdfs storage module.
* use 2.7.3
* use segment pusher to make loadspec
* move getStorageDir and makeLoad spec under DataSegmentPusher
* fix uts
* fix comment part1
* move to hadoop 2.8
* inject deep storage properties
* set version to 2.7.3
* fix build issue about static class
* fix comments
* fix default hadoop default coordinate
* fix create filesytem
* downgrade aws sdk
* bump the version
* NN optimization for hdfs data segments.
* HdfsDataSegmentKiller, HdfsDataSegment finder changes to use new storage
format.Docs update.
* Common utility function in DataSegmentPusherUtil.
* new static method `makeSegmentOutputPathUptoVersionForHdfs` in JobHelper
* reuse getHdfsStorageDirUptoVersion in
DataSegmentPusherUtil.getHdfsStorageDir()
* Addressed comments.
* Review comments.
* HdfsDataSegmentKiller requested changes.
* extra newline
* Add maprfs.
* Less use of File.deleteOnExit()
* removed deleteOnExit from most of the tests/benchmarks/iopeon
* Made IOpeon closable
* Formatting.
* Revert DeterminePartitionsJobTest, remove cleanup method from IOPeon
* fix ReleaseException when the path is being written by multiple task
* Do not throw IOException if another replica wins the race for segment creation
fix if check
* handle logging comments
* fix test
* Make URI Exctraction Namespace take more sane arguments
* Fixes https://github.com/druid-io/druid/issues/2669
* Update docs
* Rename error message
* Undo overzealous deletion of docs
* Explain caching mechanism a bit more in docs
Reverts "Update com.maxmind.geoip2 to 2.6.0" and exclude the google http client
from com.maxmind.geoip2. This should satisfy the original need from #2646 (wanting
to run Druid along with an upgraded com.google.http-client) while preventing
Jackson conflicts pointed out in #2717.
Fixes#2717.
This reverts commit 21b7572533.
* Eliminate exclusion groups from pull-deps
* Only consider dependency nodes in pull-deps if they are not in the following scopes
* provided
* test
* system
* Fix a bunch of `<scope>provided</scope>` missing tags
* Better exclusions for a couple of problematic libs
bolkedebruin
Gian Merlino
Himanshu
Jonathan Wei
Jihoon Son
David Lim
Roman Leventov
hzy001
Slim
Benedict Jin
Akash Dwivedi
Parag Jain
Roman Leventov
Nishant
Xavier Léauté
Hyukjin Kwon
Charles Allen
fjy