Fix Deadlock in HotThreadsIT#39118
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original-brownbear wants to merge 2 commits intoelastic:masterfrom
original-brownbear:experimenting-stab
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Fix Deadlock in HotThreadsIT#39118original-brownbear wants to merge 2 commits intoelastic:masterfrom original-brownbear:experimenting-stab
original-brownbear wants to merge 2 commits intoelastic:masterfrom
original-brownbear:experimenting-stab
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The way this dead-locks is: * The `size` method on the internal cluster needs a monitor on the internal cluster object in the select thread on node_1 * `client()` call on the test thread connects to node_1 at the same time, holding the monitor on the internal test cluster during the connect call * That connect can not finish because the select loop that would dispatch it is blocked waiting for the `size()` call to complete => Deadlock
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Pinging @elastic/es-distributed |
This was referenced Feb 19, 2019
DaveCTurner
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Feb 20, 2019
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DaveCTurner
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I think this is an issue in InternalTestCluster and we should try and fix it at source rather than here. If there are not already other places we call cluster().size() in a way that might lead to deadlock, there will be in future.
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@DaveCTurner fair point, a more global fix is WIP in #39168 :) (sorry for not noting this here) I'll close here, the other PR should be ready in a few minutes :) |
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The way this dead-locks is:
The
sizemethod on the internal cluster needs a monitor on the internal cluster object in the select thread on node_1client()call on the test thread connects to node_1 at the same time, holding the monitor on the internal test cluster during the connect callsize()call to complete => DeadlockCloses [CI] HotThreadsIT.testHotThreadsDontFail failure on master #37965
Relates [CI] multiple tests started failing with NoNodeAvailableException #37275
Blocked size call:
Blocked connect call (will only unblock if the above finishes since the above blocks the select loop):