[IGNITE-7845] Data race on atomicLong close

• Type: Bug
• Status: Resolved
• Priority: Major
• Resolution: Fixed
• Fix Version/s: 2.5
• Labels: MakeTeamcityGreenAgain
• Assignee: Anton Kalashnikov
• Reporter: Anton Kalashnikov
• Created: 28/Feb/18 12:26
• Updated: 10/May/18 07:48
• Resolved: 06/Mar/18 14:40

Description

Found by IgniteClientDataStructuresTest.testAtomicLong.

Given:

IgniteAtomicLong was created e.g. atomicLong = ignite.atomicLong("long1", 1L, true)

When:

IgniteAtomicLong was closed e.g. atomicLong.close()

Then:

If you try to get this value again sometimes you will get null IgniteAtomicLong value and sometimes you will get not null IgniteAtomicLong value e.g. ignite.atomicLong("long1", 1L, false) sometimes null, sometimes not null

But if we will get not null value IgniteAtomicLong and we will call method "get" on it, we will have one of two exception IllegalStateException("Sequence was removed from cache: " + name) if it already marked as deleted, and IgniteException("Failed to find atomic long: " + name) if it sill no marked as deleted but already deleted from cache.

Expected:

IgniteAtomicLong value always should be null(or not?)

Why it's happend:

When we close IgniteAtomicLong we removing value from cache in transaction but removing from internal storage(dsMap) happen asynchroniously in DataStructuresEntryListener for all nodes include local node. And when we try get value after close we still sometimes able to get IgniteAtomicLong from internal local storage.

Solution(In my opinion):

I guess in common case we don't  need call Ignite#atomicLong  every time when we need value, but we should use IgniteAtomicLong object received after first call. And if it is true, we can remove receiving IgniteAtomicLong from local storage(dsMap) - this changes will fix problem

Issue Links

• relates to: IGNITE-5977 [Test Failed] IgniteClientDiscoveryDataStructuresTest.testSequence
• links to: GitHub Pull Request #3606