This patch restores the regime instituted in original rsgroups patch
(HBASE-6721) where reading of rsgroup state runs unimpeded against
COW immutable Maps whereas mutation to state require exclusive locks
(updating the Maps of state when done). HBASE-17624 was
over-enthusiastic with its locking down of access making it likely
we'd deadlock.
Adds documentation on concurrency expectations.
Addresses review comments by Sean Busbey and Appy that happened
to come in long after the commit of HBASE-6721, the original
rsgroup issue.
Also includes subsequent accommodation of Duo Zhang review.
Adds a new type to hold hostname and port. It is called
Address. It is a facade over Guava's HostAndPort. Replace
all instances of HostAndPort with Address. In particular,
those places where HostAndPort was part of the rsgroup
public API.
Fix licenses. Add audience annotations.
Cleanup and note concurrency expectation on a few core classes.
In particular, all access on RSGroupInfoManager is made
synchronized.
M hbase-client/src/main/java/org/apache/hadoop/hbase/ServerName.java
Host the hostname and port in an instance of the new type Address.
Add a bunch of deprecation of exotic string parses that should never
have been public.
M hbase-rsgroup/src/main/java/org/apache/hadoop/hbase/rsgroup/RSGroupAdmin.java
Make this an Interface rather than abstract class. Creation was a
static internal method that only chose one type.... Let it be free
as a true Interface instead.
- Moved locks out of MasterProcedureScheduler#Queue. One Queue object is used for each namespace/table, which aren't more than 100. So we don't need complexity arising from all functionalities being in one place. SchemaLocking now owns locks and locking implementaion has been moved to procedure2 package.
- Removed NamespaceQueue because it wasn't being used as Queue (add,peek,poll,etc functions threw UnsupportedOperationException). It's was only used for locks on namespaces. Now that locks have been moved out of Queue class, it's not needed anymore.
- Remoed RegionEvent which was there only for locking on regions. Tables/namespaces used locking from Queue class and regions couldn't (there are no separate proc queue at region level), hence the redundance. Now that locking is separate, we can use the same for regions too.
- Removed QueueInterface class. No declarations, except one implementaion, which makes the point of having an interface moot.
- Removed QueueImpl, which was the only concrete implementation of abstract Queue class. Moved functions to Queue class itself to avoid unnecessary level in inheritance hierarchy.
- Removed ProcedureEventQueue class which was just a wrapper around ArrayDeque class. But we now have ProcedureWaitQueue as 'Type class'.
- Encapsulated table priority related stuff in a single class.
- Removed some unused functions.
Change-Id: I6a60424cb41e280bc111703053aa179d9071ba17
Abhishek Singh Chouhan
zhangduo
anoopsamjohn
huzheng
Sean Busbey
Jan Hentschel
Ashu Pachauri
Yu Li
tedyu
Phil Yang
rgidwani
ChiaPing Tsai
Michael Stack
Huaxiang Sun
Tim Brown
Yi Liang
Jingcheng Du
Sean Busbey
Andrew Purtell
Gary Helmling
Apekshit Sharma
Esteban Gutierrez
Enis Soztutar